Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2016 insertions, 0 deletions

diff --git a/nsprpub/pr/include/prio.h b/nsprpub/pr/include/prio.h
new file mode 100644
index 0000000000..8b331a324c
--- /dev/null
+++ b/nsprpub/pr/include/prio.h
@@ -0,0 +1,2016 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * File:     prio.h
+ *
+ * Description:    PR i/o related stuff, such as file system access, file
+ *         i/o, socket i/o, etc.
+ */
+
+#ifndef prio_h___
+#define prio_h___
+
+#include "prlong.h"
+#include "prtime.h"
+#include "prinrval.h"
+#include "prinet.h"
+
+PR_BEGIN_EXTERN_C
+
+/* Typedefs */
+typedef struct PRDir            PRDir;
+typedef struct PRDirEntry       PRDirEntry;
+#ifdef MOZ_UNICODE
+typedef struct PRDirUTF16       PRDirUTF16;
+typedef struct PRDirEntryUTF16  PRDirEntryUTF16;
+#endif /* MOZ_UNICODE */
+typedef struct PRFileDesc       PRFileDesc;
+typedef struct PRFileInfo       PRFileInfo;
+typedef struct PRFileInfo64     PRFileInfo64;
+typedef union  PRNetAddr        PRNetAddr;
+typedef struct PRIOMethods      PRIOMethods;
+typedef struct PRPollDesc       PRPollDesc;
+typedef struct PRFilePrivate    PRFilePrivate;
+typedef struct PRSendFileData   PRSendFileData;
+
+/*
+***************************************************************************
+** The file descriptor.
+** This is the primary structure to represent any active open socket,
+** whether it be a normal file or a network connection. Such objects
+** are stackable (or layerable). Each layer may have its own set of
+** method pointers and context private to that layer. All each layer
+** knows about its neighbors is how to get to their method table.
+***************************************************************************
+*/
+
+typedef PRIntn PRDescIdentity;          /* see: Layering file descriptors */
+
+struct PRFileDesc {
+    const PRIOMethods *methods;         /* the I/O methods table */
+    PRFilePrivate *secret;              /* layer dependent data */
+    PRFileDesc *lower, *higher;         /* pointers to adjacent layers */
+    void (PR_CALLBACK *dtor)(PRFileDesc *fd);
+    /* A destructor function for layer */
+    PRDescIdentity identity;            /* Identity of this particular layer  */
+};
+
+/*
+***************************************************************************
+** PRTransmitFileFlags
+**
+** Flags for PR_TransmitFile.  Pass PR_TRANSMITFILE_CLOSE_SOCKET to
+** PR_TransmitFile if the connection should be closed after the file
+** is transmitted.
+***************************************************************************
+*/
+typedef enum PRTransmitFileFlags {
+    PR_TRANSMITFILE_KEEP_OPEN = 0,    /* socket is left open after file
+                                       * is transmitted. */
+    PR_TRANSMITFILE_CLOSE_SOCKET = 1  /* socket is closed after file
+                                       * is transmitted. */
+} PRTransmitFileFlags;
+
+/*
+**************************************************************************
+** Macros for PRNetAddr
+**
+** Address families: PR_AF_INET, PR_AF_INET6, PR_AF_LOCAL
+** IP addresses: PR_INADDR_ANY, PR_INADDR_LOOPBACK, PR_INADDR_BROADCAST
+**************************************************************************
+*/
+
+#ifdef WIN32
+
+#define PR_AF_INET 2
+#define PR_AF_LOCAL 1
+#define PR_INADDR_ANY (unsigned long)0x00000000
+#define PR_INADDR_LOOPBACK 0x7f000001
+#define PR_INADDR_BROADCAST (unsigned long)0xffffffff
+
+#else /* WIN32 */
+
+#define PR_AF_INET AF_INET
+#define PR_AF_LOCAL AF_UNIX
+#define PR_INADDR_ANY INADDR_ANY
+#define PR_INADDR_LOOPBACK INADDR_LOOPBACK
+#define PR_INADDR_BROADCAST INADDR_BROADCAST
+
+#endif /* WIN32 */
+
+/*
+** Define PR_AF_INET6 in prcpucfg.h with the same
+** value as AF_INET6 on platforms with IPv6 support.
+** Otherwise define it here.
+*/
+#ifndef PR_AF_INET6
+#define PR_AF_INET6 100
+#endif
+
+#define PR_AF_INET_SDP 101
+#define PR_AF_INET6_SDP 102
+
+#ifndef PR_AF_UNSPEC
+#define PR_AF_UNSPEC 0
+#endif
+
+/*
+**************************************************************************
+** A network address
+**
+** Only Internet Protocol (IPv4 and IPv6) addresses are supported.
+** The address family must always represent IPv4 (AF_INET, probably == 2)
+** or IPv6 (AF_INET6).
+**************************************************************************
+*************************************************************************/
+
+struct PRIPv6Addr {
+    union {
+        PRUint8  _S6_u8[16];
+        PRUint16 _S6_u16[8];
+        PRUint32 _S6_u32[4];
+        PRUint64 _S6_u64[2];
+    } _S6_un;
+};
+#define pr_s6_addr      _S6_un._S6_u8
+#define pr_s6_addr16    _S6_un._S6_u16
+#define pr_s6_addr32    _S6_un._S6_u32
+#define pr_s6_addr64    _S6_un._S6_u64
+
+typedef struct PRIPv6Addr PRIPv6Addr;
+
+union PRNetAddr {
+    struct {
+        PRUint16 family;                /* address family (0x00ff maskable) */
+        char data[14];                  /* raw address data */
+    } raw;
+    struct {
+        PRUint16 family;                /* address family (AF_INET) */
+        PRUint16 port;                  /* port number */
+        PRUint32 ip;                    /* The actual 32 bits of address */
+        char pad[8];
+    } inet;
+    struct {
+        PRUint16 family;                /* address family (AF_INET6) */
+        PRUint16 port;                  /* port number */
+        PRUint32 flowinfo;              /* routing information */
+        PRIPv6Addr ip;                  /* the actual 128 bits of address */
+        PRUint32 scope_id;              /* set of interfaces for a scope */
+    } ipv6;
+#if defined(XP_UNIX) || defined(XP_OS2) || defined(XP_WIN)
+    struct {                            /* Unix domain socket address */
+        PRUint16 family;                /* address family (AF_UNIX) */
+#ifdef XP_OS2
+        char path[108];                 /* null-terminated pathname */
+        /* bind fails if size is not 108. */
+#else
+        char path[104];                 /* null-terminated pathname */
+#endif
+    } local;
+#endif
+};
+
+/*
+***************************************************************************
+** PRSockOption
+**
+** The file descriptors can have predefined options set after they file
+** descriptor is created to change their behavior. Only the options in
+** the following enumeration are supported.
+***************************************************************************
+*/
+typedef enum PRSockOption
+{
+    PR_SockOpt_Nonblocking,     /* nonblocking io */
+    PR_SockOpt_Linger,          /* linger on close if data present */
+    PR_SockOpt_Reuseaddr,       /* allow local address reuse */
+    PR_SockOpt_Keepalive,       /* keep connections alive */
+    PR_SockOpt_RecvBufferSize,  /* receive buffer size */
+    PR_SockOpt_SendBufferSize,  /* send buffer size */
+
+    PR_SockOpt_IpTimeToLive,    /* time to live */
+    PR_SockOpt_IpTypeOfService, /* type of service and precedence */
+
+    PR_SockOpt_AddMember,       /* add an IP group membership */
+    PR_SockOpt_DropMember,      /* drop an IP group membership */
+    PR_SockOpt_McastInterface,  /* multicast interface address */
+    PR_SockOpt_McastTimeToLive, /* multicast timetolive */
+    PR_SockOpt_McastLoopback,   /* multicast loopback */
+
+    PR_SockOpt_NoDelay,         /* don't delay send to coalesce packets */
+    PR_SockOpt_MaxSegment,      /* maximum segment size */
+    PR_SockOpt_Broadcast,       /* enable broadcast */
+    PR_SockOpt_Reuseport,       /* allow local address & port reuse on
+                                 * platforms that support it */
+    PR_SockOpt_DontFrag,        /* Do not fragment flag */
+    PR_SockOpt_Last
+} PRSockOption;
+
+typedef struct PRLinger {
+    PRBool polarity;            /* Polarity of the option's setting */
+    PRIntervalTime linger;      /* Time to linger before closing */
+} PRLinger;
+
+typedef struct PRMcastRequest {
+    PRNetAddr mcaddr;           /* IP multicast address of group */
+    PRNetAddr ifaddr;           /* local IP address of interface */
+} PRMcastRequest;
+
+typedef struct PRSocketOptionData
+{
+    PRSockOption option;
+    union
+    {
+        PRUintn ip_ttl;             /* IP time to live */
+        PRUintn mcast_ttl;          /* IP multicast time to live */
+        PRUintn tos;                /* IP type of service and precedence */
+        PRBool non_blocking;        /* Non-blocking (network) I/O */
+        PRBool reuse_addr;          /* Allow local address reuse */
+        PRBool reuse_port;          /* Allow local address & port reuse on
+                                     * platforms that support it */
+        PRBool dont_fragment;       /* Do not fragment flag */
+        PRBool keep_alive;          /* Keep connections alive */
+        PRBool mcast_loopback;      /* IP multicast loopback */
+        PRBool no_delay;            /* Don't delay send to coalesce packets */
+        PRBool broadcast;           /* Enable broadcast */
+        PRSize max_segment;         /* Maximum segment size */
+        PRSize recv_buffer_size;    /* Receive buffer size */
+        PRSize send_buffer_size;    /* Send buffer size */
+        PRLinger linger;            /* Time to linger on close if data present */
+        PRMcastRequest add_member;  /* add an IP group membership */
+        PRMcastRequest drop_member; /* Drop an IP group membership */
+        PRNetAddr mcast_if;         /* multicast interface address */
+    } value;
+} PRSocketOptionData;
+
+/*
+***************************************************************************
+** PRIOVec
+**
+** The I/O vector is used by the write vector method to describe the areas
+** that are affected by the ouput operation.
+***************************************************************************
+*/
+typedef struct PRIOVec {
+    char *iov_base;
+    int iov_len;
+} PRIOVec;
+
+/*
+***************************************************************************
+** Discover what type of socket is being described by the file descriptor.
+***************************************************************************
+*/
+typedef enum PRDescType
+{
+    PR_DESC_FILE = 1,
+    PR_DESC_SOCKET_TCP = 2,
+    PR_DESC_SOCKET_UDP = 3,
+    PR_DESC_LAYERED = 4,
+    PR_DESC_PIPE = 5
+} PRDescType;
+
+typedef enum PRSeekWhence {
+    PR_SEEK_SET = 0,
+    PR_SEEK_CUR = 1,
+    PR_SEEK_END = 2
+} PRSeekWhence;
+
+NSPR_API(PRDescType) PR_GetDescType(PRFileDesc *file);
+
+/*
+***************************************************************************
+** PRIOMethods
+**
+** The I/O methods table provides procedural access to the functions of
+** the file descriptor. It is the responsibility of a layer implementor
+** to provide suitable functions at every entry point. If a layer provides
+** no functionality, it should call the next lower(higher) function of the
+** same name (e.g., return fd->lower->method->close(fd->lower));
+**
+** Not all functions are implemented for all types of files. In cases where
+** that is true, the function will return a error indication with an error
+** code of PR_INVALID_METHOD_ERROR.
+***************************************************************************
+*/
+
+typedef PRStatus (PR_CALLBACK *PRCloseFN)(PRFileDesc *fd);
+typedef PRInt32 (PR_CALLBACK *PRReadFN)(PRFileDesc *fd, void *buf, PRInt32 amount);
+typedef PRInt32 (PR_CALLBACK *PRWriteFN)(PRFileDesc *fd, const void *buf, PRInt32 amount);
+typedef PRInt32 (PR_CALLBACK *PRAvailableFN)(PRFileDesc *fd);
+typedef PRInt64 (PR_CALLBACK *PRAvailable64FN)(PRFileDesc *fd);
+typedef PRStatus (PR_CALLBACK *PRFsyncFN)(PRFileDesc *fd);
+typedef PROffset32 (PR_CALLBACK *PRSeekFN)(PRFileDesc *fd, PROffset32 offset, PRSeekWhence how);
+typedef PROffset64 (PR_CALLBACK *PRSeek64FN)(PRFileDesc *fd, PROffset64 offset, PRSeekWhence how);
+typedef PRStatus (PR_CALLBACK *PRFileInfoFN)(PRFileDesc *fd, PRFileInfo *info);
+typedef PRStatus (PR_CALLBACK *PRFileInfo64FN)(PRFileDesc *fd, PRFileInfo64 *info);
+typedef PRInt32 (PR_CALLBACK *PRWritevFN)(
+    PRFileDesc *fd, const PRIOVec *iov, PRInt32 iov_size,
+    PRIntervalTime timeout);
+typedef PRStatus (PR_CALLBACK *PRConnectFN)(
+    PRFileDesc *fd, const PRNetAddr *addr, PRIntervalTime timeout);
+typedef PRFileDesc* (PR_CALLBACK *PRAcceptFN) (
+    PRFileDesc *fd, PRNetAddr *addr, PRIntervalTime timeout);
+typedef PRStatus (PR_CALLBACK *PRBindFN)(PRFileDesc *fd, const PRNetAddr *addr);
+typedef PRStatus (PR_CALLBACK *PRListenFN)(PRFileDesc *fd, PRIntn backlog);
+typedef PRStatus (PR_CALLBACK *PRShutdownFN)(PRFileDesc *fd, PRIntn how);
+typedef PRInt32 (PR_CALLBACK *PRRecvFN)(
+    PRFileDesc *fd, void *buf, PRInt32 amount,
+    PRIntn flags, PRIntervalTime timeout);
+typedef PRInt32 (PR_CALLBACK *PRSendFN) (
+    PRFileDesc *fd, const void *buf, PRInt32 amount,
+    PRIntn flags, PRIntervalTime timeout);
+typedef PRInt32 (PR_CALLBACK *PRRecvfromFN)(
+    PRFileDesc *fd, void *buf, PRInt32 amount,
+    PRIntn flags, PRNetAddr *addr, PRIntervalTime timeout);
+typedef PRInt32 (PR_CALLBACK *PRSendtoFN)(
+    PRFileDesc *fd, const void *buf, PRInt32 amount,
+    PRIntn flags, const PRNetAddr *addr, PRIntervalTime timeout);
+typedef PRInt16 (PR_CALLBACK *PRPollFN)(
+    PRFileDesc *fd, PRInt16 in_flags, PRInt16 *out_flags);
+typedef PRInt32 (PR_CALLBACK *PRAcceptreadFN)(
+    PRFileDesc *sd, PRFileDesc **nd, PRNetAddr **raddr,
+    void *buf, PRInt32 amount, PRIntervalTime t);
+typedef PRInt32 (PR_CALLBACK *PRTransmitfileFN)(
+    PRFileDesc *sd, PRFileDesc *fd, const void *headers,
+    PRInt32 hlen, PRTransmitFileFlags flags, PRIntervalTime t);
+typedef PRStatus (PR_CALLBACK *PRGetsocknameFN)(PRFileDesc *fd, PRNetAddr *addr);
+typedef PRStatus (PR_CALLBACK *PRGetpeernameFN)(PRFileDesc *fd, PRNetAddr *addr);
+typedef PRStatus (PR_CALLBACK *PRGetsocketoptionFN)(
+    PRFileDesc *fd, PRSocketOptionData *data);
+typedef PRStatus (PR_CALLBACK *PRSetsocketoptionFN)(
+    PRFileDesc *fd, const PRSocketOptionData *data);
+typedef PRInt32 (PR_CALLBACK *PRSendfileFN)(
+    PRFileDesc *networkSocket, PRSendFileData *sendData,
+    PRTransmitFileFlags flags, PRIntervalTime timeout);
+typedef PRStatus (PR_CALLBACK *PRConnectcontinueFN)(
+    PRFileDesc *fd, PRInt16 out_flags);
+typedef PRIntn (PR_CALLBACK *PRReservedFN)(PRFileDesc *fd);
+
+struct PRIOMethods {
+    PRDescType file_type;           /* Type of file represented (tos)           */
+    PRCloseFN close;                /* close file and destroy descriptor        */
+    PRReadFN read;                  /* read up to specified bytes into buffer   */
+    PRWriteFN write;                /* write specified bytes from buffer        */
+    PRAvailableFN available;        /* determine number of bytes available      */
+    PRAvailable64FN available64;    /*          ditto, 64 bit                   */
+    PRFsyncFN fsync;                /* flush all buffers to permanent store     */
+    PRSeekFN seek;                  /* position the file to the desired place   */
+    PRSeek64FN seek64;              /*           ditto, 64 bit                  */
+    PRFileInfoFN fileInfo;          /* Get information about an open file       */
+    PRFileInfo64FN fileInfo64;      /*           ditto, 64 bit                  */
+    PRWritevFN writev;              /* Write segments as described by iovector  */
+    PRConnectFN connect;            /* Connect to the specified (net) address   */
+    PRAcceptFN accept;              /* Accept a connection for a (net) peer     */
+    PRBindFN bind;                  /* Associate a (net) address with the fd    */
+    PRListenFN listen;              /* Prepare to listen for (net) connections  */
+    PRShutdownFN shutdown;          /* Shutdown a (net) connection              */
+    PRRecvFN recv;                  /* Solicit up the the specified bytes       */
+    PRSendFN send;                  /* Send all the bytes specified             */
+    PRRecvfromFN recvfrom;          /* Solicit (net) bytes and report source    */
+    PRSendtoFN sendto;              /* Send bytes to (net) address specified    */
+    PRPollFN poll;                  /* Test the fd to see if it is ready        */
+    PRAcceptreadFN acceptread;      /* Accept and read on a new (net) fd        */
+    PRTransmitfileFN transmitfile;  /* Transmit at entire file                  */
+    PRGetsocknameFN getsockname;    /* Get (net) address associated with fd     */
+    PRGetpeernameFN getpeername;    /* Get peer's (net) address                 */
+    PRReservedFN reserved_fn_6;     /* reserved for future use */
+    PRReservedFN reserved_fn_5;     /* reserved for future use */
+    PRGetsocketoptionFN getsocketoption;
+    /* Get current setting of specified option  */
+    PRSetsocketoptionFN setsocketoption;
+    /* Set value of specified option            */
+    PRSendfileFN sendfile;          /* Send a (partial) file with header/trailer*/
+    PRConnectcontinueFN connectcontinue;
+    /* Continue a nonblocking connect */
+    PRReservedFN reserved_fn_3;     /* reserved for future use */
+    PRReservedFN reserved_fn_2;     /* reserved for future use */
+    PRReservedFN reserved_fn_1;     /* reserved for future use */
+    PRReservedFN reserved_fn_0;     /* reserved for future use */
+};
+
+/*
+ **************************************************************************
+ * FUNCTION: PR_GetSpecialFD
+ * DESCRIPTION: Get the file descriptor that represents the standard input,
+ *              output, or error stream.
+ * INPUTS:
+ *     PRSpecialFD id
+ *         A value indicating the type of stream desired:
+ *             PR_StandardInput: standard input
+ *             PR_StandardOuput: standard output
+ *             PR_StandardError: standard error
+ * OUTPUTS: none
+ * RETURNS: PRFileDesc *
+ *     If the argument is valid, PR_GetSpecialFD returns a file descriptor
+ *     that represents the corresponding standard I/O stream.  Otherwise,
+ *     PR_GetSpecialFD returns NULL and sets error PR_INVALID_ARGUMENT_ERROR.
+ **************************************************************************
+ */
+
+typedef enum PRSpecialFD
+{
+    PR_StandardInput,          /* standard input */
+    PR_StandardOutput,         /* standard output */
+    PR_StandardError           /* standard error */
+} PRSpecialFD;
+
+NSPR_API(PRFileDesc*) PR_GetSpecialFD(PRSpecialFD id);
+
+#define PR_STDIN    PR_GetSpecialFD(PR_StandardInput)
+#define PR_STDOUT   PR_GetSpecialFD(PR_StandardOutput)
+#define PR_STDERR   PR_GetSpecialFD(PR_StandardError)
+
+/*
+ **************************************************************************
+ * Layering file descriptors
+ *
+ * File descriptors may be layered. Each layer has it's own identity.
+ * Identities are allocated by the runtime and are to be associated
+ * (by the layer implementor) with all layers that are of that type.
+ * It is then possible to scan the chain of layers and find a layer
+ * that one recongizes and therefore predict that it will implement
+ * a desired protocol.
+ *
+ * There are three well-known identities:
+ *      PR_INVALID_IO_LAYER => an invalid layer identity, for error return
+ *      PR_TOP_IO_LAYER     => the identity of the top of the stack
+ *      PR_NSPR_IO_LAYER    => the identity used by NSPR proper
+ * PR_TOP_IO_LAYER may be used as a shorthand for identifying the topmost
+ * layer of an existing stack. Ie., the following two constructs are
+ * equivalent.
+ *
+ *      rv = PR_PushIOLayer(stack, PR_TOP_IO_LAYER, my_layer);
+ *      rv = PR_PushIOLayer(stack, PR_GetLayersIdentity(stack), my_layer)
+ *
+ * A string may be associated with the creation of the identity. It
+ * will be copied by the runtime. If queried the runtime will return
+ * a reference to that copied string (not yet another copy). There
+ * is no facility for deleting an identity.
+ **************************************************************************
+ */
+
+#define PR_IO_LAYER_HEAD (PRDescIdentity)-3
+#define PR_INVALID_IO_LAYER (PRDescIdentity)-1
+#define PR_TOP_IO_LAYER (PRDescIdentity)-2
+#define PR_NSPR_IO_LAYER (PRDescIdentity)0
+
+NSPR_API(PRDescIdentity) PR_GetUniqueIdentity(const char *layer_name);
+NSPR_API(const char*) PR_GetNameForIdentity(PRDescIdentity ident);
+NSPR_API(PRDescIdentity) PR_GetLayersIdentity(PRFileDesc* fd);
+NSPR_API(PRFileDesc*) PR_GetIdentitiesLayer(PRFileDesc* fd_stack, PRDescIdentity id);
+
+/*
+ **************************************************************************
+ * PR_GetDefaultIOMethods: Accessing the default methods table.
+ * You may get a pointer to the default methods table by calling this function.
+ * You may then select any elements from that table with which to build your
+ * layer's methods table. You may NOT modify the table directly.
+ **************************************************************************
+ */
+NSPR_API(const PRIOMethods *) PR_GetDefaultIOMethods(void);
+
+/*
+ **************************************************************************
+ * Creating a layer
+ *
+ * A new layer may be allocated by calling PR_CreateIOLayerStub(). The
+ * file descriptor returned will contain the pointer to the methods table
+ * provided. The runtime will not modify the table nor test its correctness.
+ **************************************************************************
+ */
+NSPR_API(PRFileDesc*) PR_CreateIOLayerStub(
+    PRDescIdentity ident, const PRIOMethods *methods);
+
+/*
+ **************************************************************************
+ * Creating a layer
+ *
+ * A new stack may be created by calling PR_CreateIOLayer(). The
+ * file descriptor returned will point to the top of the stack, which has
+ * the layer 'fd' as the topmost layer.
+ *
+ * NOTE: This function creates a new style stack, which has a fixed, dummy
+ * header. The old style stack, created by a call to PR_PushIOLayer,
+ * results in modifying contents of the top layer of the stack, when
+ * pushing and popping layers of the stack.
+ **************************************************************************
+ */
+NSPR_API(PRFileDesc*) PR_CreateIOLayer(PRFileDesc* fd);
+
+/*
+ **************************************************************************
+ * Pushing a layer
+ *
+ * A file descriptor (perhaps allocated using PR_CreateIOLayerStub()) may
+ * be pushed into an existing stack of file descriptors at any point the
+ * caller deems appropriate. The new layer will be inserted into the stack
+ * just above the layer with the indicated identity.
+ *
+ * Note: Even if the identity parameter indicates the top-most layer of
+ * the stack, the value of the file descriptor describing the original
+ * stack will not change.
+ **************************************************************************
+ */
+NSPR_API(PRStatus) PR_PushIOLayer(
+    PRFileDesc *fd_stack, PRDescIdentity id, PRFileDesc *layer);
+
+/*
+ **************************************************************************
+ * Popping a layer
+ *
+ * A layer may be popped from a stack by indicating the identity of the
+ * layer to be removed. If found, a pointer to the removed object will
+ * be returned to the caller. The object then becomes the responsibility
+ * of the caller.
+ *
+ * Note: Even if the identity indicates the top layer of the stack, the
+ * reference returned will not be the file descriptor for the stack and
+ * that file descriptor will remain valid.
+ **************************************************************************
+ */
+NSPR_API(PRFileDesc*) PR_PopIOLayer(PRFileDesc *fd_stack, PRDescIdentity id);
+
+/*
+ **************************************************************************
+ * FUNCTION:    PR_Open
+ * DESCRIPTION:    Open a file for reading, writing, or both.
+ * INPUTS:
+ *     const char *name
+ *         The path name of the file to be opened
+ *     PRIntn flags
+ *         The file status flags.
+ *         It is a bitwise OR of the following bit flags (only one of
+ *         the first three flags below may be used):
+ *      PR_RDONLY        Open for reading only.
+ *      PR_WRONLY        Open for writing only.
+ *      PR_RDWR          Open for reading and writing.
+ *      PR_CREATE_FILE   If the file does not exist, the file is created
+ *                              If the file exists, this flag has no effect.
+ *      PR_SYNC          If set, each write will wait for both the file data
+ *                              and file status to be physically updated.
+ *      PR_APPEND        The file pointer is set to the end of
+ *                              the file prior to each write.
+ *      PR_TRUNCATE      If the file exists, its length is truncated to 0.
+ *      PR_EXCL          With PR_CREATE_FILE, if the file does not exist,
+ *                              the file is created. If the file already
+ *                              exists, no action and NULL is returned
+ *
+ *     PRIntn mode
+ *         The access permission bits of the file mode, if the file is
+ *         created when PR_CREATE_FILE is on.
+ * OUTPUTS:    None
+ * RETURNS:    PRFileDesc *
+ *     If the file is successfully opened,
+ *     returns a pointer to the PRFileDesc
+ *     created for the newly opened file.
+ *     Returns a NULL pointer if the open
+ *     failed.
+ * SIDE EFFECTS:
+ * RESTRICTIONS:
+ * MEMORY:
+ *     The return value, if not NULL, points to a dynamically allocated
+ *     PRFileDesc object.
+ * ALGORITHM:
+ **************************************************************************
+ */
+
+/* Open flags */
+#define PR_RDONLY       0x01
+#define PR_WRONLY       0x02
+#define PR_RDWR         0x04
+#define PR_CREATE_FILE  0x08
+#define PR_APPEND       0x10
+#define PR_TRUNCATE     0x20
+#define PR_SYNC         0x40
+#define PR_EXCL         0x80
+
+/*
+** File modes ....
+**
+** CAVEAT: 'mode' is currently only applicable on UNIX platforms.
+** The 'mode' argument may be ignored by PR_Open on other platforms.
+**
+**   00400   Read by owner.
+**   00200   Write by owner.
+**   00100   Execute (search if a directory) by owner.
+**   00040   Read by group.
+**   00020   Write by group.
+**   00010   Execute by group.
+**   00004   Read by others.
+**   00002   Write by others
+**   00001   Execute by others.
+**
+*/
+
+NSPR_API(PRFileDesc*) PR_Open(const char *name, PRIntn flags, PRIntn mode);
+
+/*
+ **************************************************************************
+ * FUNCTION: PR_OpenFile
+ * DESCRIPTION:
+ *     Open a file for reading, writing, or both.
+ *     PR_OpenFile has the same prototype as PR_Open but implements
+ *     the specified file mode where possible.
+ **************************************************************************
+ */
+
+/* File mode bits */
+#define PR_IRWXU 00700  /* read, write, execute/search by owner */
+#define PR_IRUSR 00400  /* read permission, owner */
+#define PR_IWUSR 00200  /* write permission, owner */
+#define PR_IXUSR 00100  /* execute/search permission, owner */
+#define PR_IRWXG 00070  /* read, write, execute/search by group */
+#define PR_IRGRP 00040  /* read permission, group */
+#define PR_IWGRP 00020  /* write permission, group */
+#define PR_IXGRP 00010  /* execute/search permission, group */
+#define PR_IRWXO 00007  /* read, write, execute/search by others */
+#define PR_IROTH 00004  /* read permission, others */
+#define PR_IWOTH 00002  /* write permission, others */
+#define PR_IXOTH 00001  /* execute/search permission, others */
+
+NSPR_API(PRFileDesc*) PR_OpenFile(
+    const char *name, PRIntn flags, PRIntn mode);
+
+#ifdef MOZ_UNICODE
+/*
+ * EXPERIMENTAL: This function may be removed in a future release.
+ */
+NSPR_API(PRFileDesc*) PR_OpenFileUTF16(
+    const PRUnichar *name, PRIntn flags, PRIntn mode);
+#endif /* MOZ_UNICODE */
+
+/*
+ **************************************************************************
+ * FUNCTION: PR_Close
+ * DESCRIPTION:
+ *     Close a file or socket.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *         a pointer to a PRFileDesc.
+ * OUTPUTS:
+ *     None.
+ * RETURN:
+ *     PRStatus
+ * SIDE EFFECTS:
+ * RESTRICTIONS:
+ *     None.
+ * MEMORY:
+ *     The dynamic memory pointed to by the argument fd is freed.
+ **************************************************************************
+ */
+
+NSPR_API(PRStatus)    PR_Close(PRFileDesc *fd);
+
+/*
+ **************************************************************************
+ * FUNCTION: PR_Read
+ * DESCRIPTION:
+ *     Read bytes from a file or socket.
+ *     The operation will block until either an end of stream indication is
+ *     encountered, some positive number of bytes are transferred, or there
+ *     is an error. No more than 'amount' bytes will be transferred.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *         pointer to the PRFileDesc object for the file or socket
+ *     void *buf
+ *         pointer to a buffer to hold the data read in.
+ *     PRInt32 amount
+ *         the size of 'buf' (in bytes)
+ * OUTPUTS:
+ * RETURN:
+ *     PRInt32
+ *         a positive number indicates the number of bytes actually read in.
+ *         0 means end of file is reached or the network connection is closed.
+ *         -1 indicates a failure. The reason for the failure is obtained
+ *         by calling PR_GetError().
+ * SIDE EFFECTS:
+ *     data is written into the buffer pointed to by 'buf'.
+ * RESTRICTIONS:
+ *     None.
+ * MEMORY:
+ *     N/A
+ * ALGORITHM:
+ *     N/A
+ **************************************************************************
+ */
+
+NSPR_API(PRInt32) PR_Read(PRFileDesc *fd, void *buf, PRInt32 amount);
+
+/*
+ ***************************************************************************
+ * FUNCTION: PR_Write
+ * DESCRIPTION:
+ *     Write a specified number of bytes to a file or socket.  The thread
+ *     invoking this function blocks until all the data is written.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *         pointer to a PRFileDesc object that refers to a file or socket
+ *     const void *buf
+ *         pointer to the buffer holding the data
+ *     PRInt32 amount
+ *         amount of data in bytes to be written from the buffer
+ * OUTPUTS:
+ *     None.
+ * RETURN: PRInt32
+ *     A positive number indicates the number of bytes successfully written.
+ *     A -1 is an indication that the operation failed. The reason
+ *     for the failure is obtained by calling PR_GetError().
+ ***************************************************************************
+ */
+
+NSPR_API(PRInt32) PR_Write(PRFileDesc *fd,const void *buf,PRInt32 amount);
+
+/*
+ ***************************************************************************
+ * FUNCTION: PR_Writev
+ * DESCRIPTION:
+ *     Write data to a socket.  The data is organized in a PRIOVec array. The
+ *     operation will block until all the data is written or the operation
+ *     fails.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *         Pointer that points to a PRFileDesc object for a socket.
+ *     const PRIOVec *iov
+ *         An array of PRIOVec.  PRIOVec is a struct with the following
+ *         two fields:
+ *             char *iov_base;
+ *             int iov_len;
+ *     PRInt32 iov_size
+ *         Number of elements in the iov array. The value of this
+ *         argument must not be greater than PR_MAX_IOVECTOR_SIZE.
+ *         If it is, the method will fail (PR_BUFFER_OVERFLOW_ERROR).
+ *     PRIntervalTime timeout
+ *       Time limit for completion of the entire write operation.
+ * OUTPUTS:
+ *     None
+ * RETURN:
+ *     A positive number indicates the number of bytes successfully written.
+ *     A -1 is an indication that the operation failed. The reason
+ *     for the failure is obtained by calling PR_GetError().
+ ***************************************************************************
+ */
+
+#define PR_MAX_IOVECTOR_SIZE 16   /* 'iov_size' must be <= */
+
+NSPR_API(PRInt32) PR_Writev(
+    PRFileDesc *fd, const PRIOVec *iov, PRInt32 iov_size,
+    PRIntervalTime timeout);
+
+/*
+ ***************************************************************************
+ * FUNCTION: PR_Delete
+ * DESCRIPTION:
+ *     Delete a file from the filesystem. The operation may fail if the
+ *     file is open.
+ * INPUTS:
+ *     const char *name
+ *         Path name of the file to be deleted.
+ * OUTPUTS:
+ *     None.
+ * RETURN: PRStatus
+ *     The function returns PR_SUCCESS if the file is successfully
+ *     deleted, otherwise it returns PR_FAILURE.
+ ***************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_Delete(const char *name);
+
+/**************************************************************************/
+
+typedef enum PRFileType
+{
+    PR_FILE_FILE = 1,
+    PR_FILE_DIRECTORY = 2,
+    PR_FILE_OTHER = 3
+} PRFileType;
+
+struct PRFileInfo {
+    PRFileType type;        /* Type of file */
+    PROffset32 size;        /* Size, in bytes, of file's contents */
+    PRTime creationTime;    /* Creation time per definition of PRTime */
+    PRTime modifyTime;      /* Last modification time per definition of PRTime */
+};
+
+struct PRFileInfo64 {
+    PRFileType type;        /* Type of file */
+    PROffset64 size;        /* Size, in bytes, of file's contents */
+    PRTime creationTime;    /* Creation time per definition of PRTime */
+    PRTime modifyTime;      /* Last modification time per definition of PRTime */
+};
+
+/****************************************************************************
+ * FUNCTION: PR_GetFileInfo, PR_GetFileInfo64
+ * DESCRIPTION:
+ *     Get the information about the file with the given path name. This is
+ *     applicable only to NSFileDesc describing 'file' types (see
+ * INPUTS:
+ *     const char *fn
+ *         path name of the file
+ * OUTPUTS:
+ *     PRFileInfo *info
+ *         Information about the given file is written into the file
+ *         information object pointer to by 'info'.
+ * RETURN: PRStatus
+ *     PR_GetFileInfo returns PR_SUCCESS if file information is successfully
+ *     obtained, otherwise it returns PR_FAILURE.
+ ***************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_GetFileInfo(const char *fn, PRFileInfo *info);
+NSPR_API(PRStatus) PR_GetFileInfo64(const char *fn, PRFileInfo64 *info);
+
+#ifdef MOZ_UNICODE
+/*
+ * EXPERIMENTAL: This function may be removed in a future release.
+ */
+NSPR_API(PRStatus) PR_GetFileInfo64UTF16(const PRUnichar *fn, PRFileInfo64 *info);
+#endif /* MOZ_UNICODE */
+
+/*
+ **************************************************************************
+ * FUNCTION: PR_GetOpenFileInfo, PR_GetOpenFileInfo64
+ * DESCRIPTION:
+ *     Get information about an open file referred to by the
+ *     given PRFileDesc object.
+ * INPUTS:
+ *     const PRFileDesc *fd
+ *          A reference to a valid, open file.
+ * OUTPUTS:
+ *     Same as PR_GetFileInfo, PR_GetFileInfo64
+ * RETURN: PRStatus
+ *     PR_GetFileInfo returns PR_SUCCESS if file information is successfully
+ *     obtained, otherwise it returns PR_FAILURE.
+ ***************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_GetOpenFileInfo(PRFileDesc *fd, PRFileInfo *info);
+NSPR_API(PRStatus) PR_GetOpenFileInfo64(PRFileDesc *fd, PRFileInfo64 *info);
+
+/*
+ **************************************************************************
+ * FUNCTION: PR_Rename
+ * DESCRIPTION:
+ *     Rename a file from the old name 'from' to the new name 'to'.
+ * INPUTS:
+ *     const char *from
+ *         The old name of the file to be renamed.
+ *     const char *to
+ *         The new name of the file.
+ * OUTPUTS:
+ *     None.
+ * RETURN: PRStatus
+ **************************************************************************
+ */
+
+NSPR_API(PRStatus)    PR_Rename(const char *from, const char *to);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_Access
+ * DESCRIPTION:
+ *     Determine accessibility of a file.
+ * INPUTS:
+ *     const char *name
+ *         path name of the file
+ *     PRAccessHow how
+ *         specifies which access permission to check for.
+ *         It can be one of the following values:
+ *             PR_ACCESS_READ_OK       Test for read permission
+ *             PR_ACCESS_WRITE_OK      Test for write permission
+ *             PR_ACCESS_EXISTS        Check existence of file
+ * OUTPUTS:
+ *     None.
+ * RETURN: PRStatus
+ *     PR_SUCCESS is returned if the requested access is permitted.
+ *     Otherwise, PR_FAILURE is returned. Additional information
+ *     regarding the reason for the failure may be retrieved from
+ *     PR_GetError().
+ *************************************************************************
+ */
+
+typedef enum PRAccessHow {
+    PR_ACCESS_EXISTS = 1,
+    PR_ACCESS_WRITE_OK = 2,
+    PR_ACCESS_READ_OK = 3
+} PRAccessHow;
+
+NSPR_API(PRStatus) PR_Access(const char *name, PRAccessHow how);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_Seek, PR_Seek64
+ * DESCRIPTION:
+ *     Moves read-write file offset
+ * INPUTS:
+ *     PRFileDesc *fd
+ *         Pointer to a PRFileDesc object.
+ *     PROffset32, PROffset64 offset
+ *         Specifies a value, in bytes, that is used in conjunction
+ *         with the 'whence' parameter to set the file pointer.  A
+ *         negative value causes seeking in the reverse direction.
+ *     PRSeekWhence whence
+ *         Specifies how to interpret the 'offset' parameter in setting
+ *         the file pointer associated with the 'fd' parameter.
+ *         Values for the 'whence' parameter are:
+ *             PR_SEEK_SET  Sets the file pointer to the value of the
+ *                          'offset' parameter
+ *             PR_SEEK_CUR  Sets the file pointer to its current location
+ *                          plus the value of the offset parameter.
+ *             PR_SEEK_END  Sets the file pointer to the size of the
+ *                          file plus the value of the offset parameter.
+ * OUTPUTS:
+ *     None.
+ * RETURN: PROffset32, PROffset64
+ *     Upon successful completion, the resulting pointer location,
+ *     measured in bytes from the beginning of the file, is returned.
+ *     If the PR_Seek() function fails, the file offset remains
+ *     unchanged, and the returned value is -1. The error code can
+ *     then be retrieved via PR_GetError().
+ *************************************************************************
+ */
+
+NSPR_API(PROffset32) PR_Seek(PRFileDesc *fd, PROffset32 offset, PRSeekWhence whence);
+NSPR_API(PROffset64) PR_Seek64(PRFileDesc *fd, PROffset64 offset, PRSeekWhence whence);
+
+/*
+ ************************************************************************
+ * FUNCTION: PR_Available
+ * DESCRIPTION:
+ *     Determine the amount of data in bytes available for reading
+ *     in the given file or socket.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *         Pointer to a PRFileDesc object that refers to a file or
+ *         socket.
+ * OUTPUTS:
+ *     None
+ * RETURN: PRInt32, PRInt64
+ *     Upon successful completion, PR_Available returns the number of
+ *     bytes beyond the current read pointer that is available for
+ *     reading.  Otherwise, it returns a -1 and the reason for the
+ *     failure can be retrieved via PR_GetError().
+ ************************************************************************
+ */
+
+NSPR_API(PRInt32) PR_Available(PRFileDesc *fd);
+NSPR_API(PRInt64) PR_Available64(PRFileDesc *fd);
+
+/*
+ ************************************************************************
+ * FUNCTION: PR_Sync
+ * DESCRIPTION:
+ *     Sync any buffered data for a fd to its backing device (disk).
+ * INPUTS:
+ *     PRFileDesc *fd
+ *         Pointer to a PRFileDesc object that refers to a file or
+ *         socket
+ * OUTPUTS:
+ *     None
+ * RETURN: PRStatus
+ *     PR_SUCCESS is returned if the requested access is permitted.
+ *     Otherwise, PR_FAILURE is returned.
+ ************************************************************************
+ */
+
+NSPR_API(PRStatus)  PR_Sync(PRFileDesc *fd);
+
+/************************************************************************/
+
+struct PRDirEntry {
+    const char *name;        /* name of entry, relative to directory name */
+};
+
+#ifdef MOZ_UNICODE
+struct PRDirEntryUTF16 {
+    const PRUnichar *name;   /* name of entry in UTF16, relative to
+                              * directory name */
+};
+#endif /* MOZ_UNICODE */
+
+#if !defined(NO_NSPR_10_SUPPORT)
+#define PR_DirName(dirEntry)    (dirEntry->name)
+#endif
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_OpenDir
+ * DESCRIPTION:
+ *     Open the directory by the given name
+ * INPUTS:
+ *     const char *name
+ *         path name of the directory to be opened
+ * OUTPUTS:
+ *     None
+ * RETURN: PRDir *
+ *     If the directory is sucessfully opened, a PRDir object is
+ *     dynamically allocated and a pointer to it is returned.
+ *     If the directory cannot be opened, a NULL pointer is returned.
+ * MEMORY:
+ *     Upon successful completion, the return value points to
+ *     dynamically allocated memory.
+ *************************************************************************
+ */
+
+NSPR_API(PRDir*) PR_OpenDir(const char *name);
+
+#ifdef MOZ_UNICODE
+/*
+ * EXPERIMENTAL: This function may be removed in a future release.
+ */
+NSPR_API(PRDirUTF16*) PR_OpenDirUTF16(const PRUnichar *name);
+#endif /* MOZ_UNICODE */
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_ReadDir
+ * DESCRIPTION:
+ * INPUTS:
+ *     PRDir *dir
+ *         pointer to a PRDir object that designates an open directory
+ *     PRDirFlags flags
+ *           PR_SKIP_NONE     Do not skip any files
+ *           PR_SKIP_DOT      Skip the directory entry "." that
+ *                            represents the current directory
+ *           PR_SKIP_DOT_DOT  Skip the directory entry ".." that
+ *                            represents the parent directory.
+ *           PR_SKIP_BOTH     Skip both '.' and '..'
+ *           PR_SKIP_HIDDEN   Skip hidden files
+ * OUTPUTS:
+ * RETURN: PRDirEntry*
+ *     Returns a pointer to the next entry in the directory.  Returns
+ *     a NULL pointer upon reaching the end of the directory or when an
+ *     error occurs. The actual reason can be retrieved via PR_GetError().
+ *************************************************************************
+ */
+
+typedef enum PRDirFlags {
+    PR_SKIP_NONE = 0x0,
+    PR_SKIP_DOT = 0x1,
+    PR_SKIP_DOT_DOT = 0x2,
+    PR_SKIP_BOTH = 0x3,
+    PR_SKIP_HIDDEN = 0x4
+} PRDirFlags;
+
+NSPR_API(PRDirEntry*) PR_ReadDir(PRDir *dir, PRDirFlags flags);
+
+#ifdef MOZ_UNICODE
+/*
+ * EXPERIMENTAL: This function may be removed in a future release.
+ */
+NSPR_API(PRDirEntryUTF16*) PR_ReadDirUTF16(PRDirUTF16 *dir, PRDirFlags flags);
+#endif /* MOZ_UNICODE */
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_CloseDir
+ * DESCRIPTION:
+ *     Close the specified directory.
+ * INPUTS:
+ *     PRDir *dir
+ *        The directory to be closed.
+ * OUTPUTS:
+ *     None
+ * RETURN: PRStatus
+ *        If successful, will return a status of PR_SUCCESS. Otherwise
+ *        a value of PR_FAILURE. The reason for the failure may be re-
+ *        trieved using PR_GetError().
+ *************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_CloseDir(PRDir *dir);
+
+#ifdef MOZ_UNICODE
+/*
+ * EXPERIMENTAL: This function may be removed in a future release.
+ */
+NSPR_API(PRStatus) PR_CloseDirUTF16(PRDirUTF16 *dir);
+#endif /* MOZ_UNICODE */
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_MkDir
+ * DESCRIPTION:
+ *     Create a new directory with the given name and access mode.
+ * INPUTS:
+ *     const char *name
+ *        The name of the directory to be created. All the path components
+ *        up to but not including the leaf component must already exist.
+ *     PRIntn mode
+ *        See 'mode' definiton in PR_Open().
+ * OUTPUTS:
+ *     None
+ * RETURN: PRStatus
+ *        If successful, will return a status of PR_SUCCESS. Otherwise
+ *        a value of PR_FAILURE. The reason for the failure may be re-
+ *        trieved using PR_GetError().
+ *************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_MkDir(const char *name, PRIntn mode);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_MakeDir
+ * DESCRIPTION:
+ *     Create a new directory with the given name and access mode.
+ *     PR_MakeDir has the same prototype as PR_MkDir but implements
+ *     the specified access mode where possible.
+ *************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_MakeDir(const char *name, PRIntn mode);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_RmDir
+ * DESCRIPTION:
+ *     Remove a directory by the given name.
+ * INPUTS:
+ *     const char *name
+ *        The name of the directory to be removed. All the path components
+ *        must already exist. Only the leaf component will be removed.
+ * OUTPUTS:
+ *     None
+ * RETURN: PRStatus
+ *        If successful, will return a status of PR_SUCCESS. Otherwise
+ *        a value of PR_FAILURE. The reason for the failure may be re-
+ *        trieved using PR_GetError().
+ **************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_RmDir(const char *name);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_NewUDPSocket
+ * DESCRIPTION:
+ *     Create a new UDP socket.
+ * INPUTS:
+ *     None
+ * OUTPUTS:
+ *     None
+ * RETURN: PRFileDesc*
+ *     Upon successful completion, PR_NewUDPSocket returns a pointer
+ *     to the PRFileDesc created for the newly opened UDP socket.
+ *     Returns a NULL pointer if the creation of a new UDP socket failed.
+ *
+ **************************************************************************
+ */
+
+NSPR_API(PRFileDesc*)    PR_NewUDPSocket(void);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_NewTCPSocket
+ * DESCRIPTION:
+ *     Create a new TCP socket.
+ * INPUTS:
+ *     None
+ * OUTPUTS:
+ *     None
+ * RETURN: PRFileDesc*
+ *     Upon successful completion, PR_NewTCPSocket returns a pointer
+ *     to the PRFileDesc created for the newly opened TCP socket.
+ *     Returns a NULL pointer if the creation of a new TCP socket failed.
+ *
+ **************************************************************************
+ */
+
+NSPR_API(PRFileDesc*)    PR_NewTCPSocket(void);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_OpenUDPSocket
+ * DESCRIPTION:
+ *     Create a new UDP socket of the specified address family.
+ * INPUTS:
+ *     PRIntn af
+ *       Address family
+ * OUTPUTS:
+ *     None
+ * RETURN: PRFileDesc*
+ *     Upon successful completion, PR_OpenUDPSocket returns a pointer
+ *     to the PRFileDesc created for the newly opened UDP socket.
+ *     Returns a NULL pointer if the creation of a new UDP socket failed.
+ *
+ **************************************************************************
+ */
+
+NSPR_API(PRFileDesc*)    PR_OpenUDPSocket(PRIntn af);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_OpenTCPSocket
+ * DESCRIPTION:
+ *     Create a new TCP socket of the specified address family.
+ * INPUTS:
+ *     PRIntn af
+ *       Address family
+ * OUTPUTS:
+ *     None
+ * RETURN: PRFileDesc*
+ *     Upon successful completion, PR_NewTCPSocket returns a pointer
+ *     to the PRFileDesc created for the newly opened TCP socket.
+ *     Returns a NULL pointer if the creation of a new TCP socket failed.
+ *
+ **************************************************************************
+ */
+
+NSPR_API(PRFileDesc*)    PR_OpenTCPSocket(PRIntn af);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_Connect
+ * DESCRIPTION:
+ *     Initiate a connection on a socket.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       Points to a PRFileDesc object representing a socket
+ *     PRNetAddr *addr
+ *       Specifies the address of the socket in its own communication
+ *       space.
+ *     PRIntervalTime timeout
+ *       The function uses the lesser of the provided timeout and
+ *       the OS's connect timeout.  In particular, if you specify
+ *       PR_INTERVAL_NO_TIMEOUT as the timeout, the OS's connection
+ *       time limit will be used.
+ *
+ * OUTPUTS:
+ *     None
+ * RETURN: PRStatus
+ *     Upon successful completion of connection initiation, PR_Connect
+ *     returns PR_SUCCESS.  Otherwise, it returns PR_FAILURE.  Further
+ *     failure information can be obtained by calling PR_GetError().
+ **************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_Connect(
+    PRFileDesc *fd, const PRNetAddr *addr, PRIntervalTime timeout);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_ConnectContinue
+ * DESCRIPTION:
+ *     Continue a nonblocking connect.  After a nonblocking connect
+ *     is initiated with PR_Connect() (which fails with
+ *     PR_IN_PROGRESS_ERROR), one should call PR_Poll() on the socket,
+ *     with the in_flags PR_POLL_WRITE | PR_POLL_EXCEPT.  When
+ *     PR_Poll() returns, one calls PR_ConnectContinue() on the
+ *     socket to determine whether the nonblocking connect has
+ *     completed or is still in progress.  Repeat the PR_Poll(),
+ *     PR_ConnectContinue() sequence until the nonblocking connect
+ *     has completed.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *         the file descriptor representing a socket
+ *     PRInt16 out_flags
+ *         the out_flags field of the poll descriptor returned by
+ *         PR_Poll()
+ * RETURN: PRStatus
+ *     If the nonblocking connect has successfully completed,
+ *     PR_ConnectContinue returns PR_SUCCESS.  If PR_ConnectContinue()
+ *     returns PR_FAILURE, call PR_GetError():
+ *     - PR_IN_PROGRESS_ERROR: the nonblocking connect is still in
+ *       progress and has not completed yet.  The caller should poll
+ *       on the file descriptor for the in_flags
+ *       PR_POLL_WRITE|PR_POLL_EXCEPT and retry PR_ConnectContinue
+ *       later when PR_Poll() returns.
+ *     - Other errors: the nonblocking connect has failed with this
+ *       error code.
+ */
+
+NSPR_API(PRStatus)    PR_ConnectContinue(PRFileDesc *fd, PRInt16 out_flags);
+
+/*
+ *************************************************************************
+ * THIS FUNCTION IS DEPRECATED.  USE PR_ConnectContinue INSTEAD.
+ *
+ * FUNCTION: PR_GetConnectStatus
+ * DESCRIPTION:
+ *     Get the completion status of a nonblocking connect.  After
+ *     a nonblocking connect is initiated with PR_Connect() (which
+ *     fails with PR_IN_PROGRESS_ERROR), one should call PR_Poll()
+ *     on the socket, with the in_flags PR_POLL_WRITE | PR_POLL_EXCEPT.
+ *     When PR_Poll() returns, one calls PR_GetConnectStatus on the
+ *     PRPollDesc structure to determine whether the nonblocking
+ *     connect has succeeded or failed.
+ * INPUTS:
+ *     const PRPollDesc *pd
+ *         Pointer to a PRPollDesc whose fd member is the socket,
+ *         and in_flags must contain PR_POLL_WRITE and PR_POLL_EXCEPT.
+ *         PR_Poll() should have been called and set the out_flags.
+ * RETURN: PRStatus
+ *     If the nonblocking connect has successfully completed,
+ *     PR_GetConnectStatus returns PR_SUCCESS.  If PR_GetConnectStatus()
+ *     returns PR_FAILURE, call PR_GetError():
+ *     - PR_IN_PROGRESS_ERROR: the nonblocking connect is still in
+ *       progress and has not completed yet.
+ *     - Other errors: the nonblocking connect has failed with this
+ *       error code.
+ */
+
+NSPR_API(PRStatus)    PR_GetConnectStatus(const PRPollDesc *pd);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_Accept
+ * DESCRIPTION:
+ *     Accept a connection on a socket.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       Points to a PRFileDesc object representing the rendezvous socket
+ *       on which the caller is willing to accept new connections.
+ *     PRIntervalTime timeout
+ *       Time limit for completion of the accept operation.
+ * OUTPUTS:
+ *     PRNetAddr *addr
+ *       Returns the address of the connecting entity in its own
+ *       communication space. It may be NULL.
+ * RETURN: PRFileDesc*
+ *     Upon successful acceptance of a connection, PR_Accept
+ *     returns a valid file descriptor. Otherwise, it returns NULL.
+ *     Further failure information can be obtained by calling PR_GetError().
+ **************************************************************************
+ */
+
+NSPR_API(PRFileDesc*) PR_Accept(
+    PRFileDesc *fd, PRNetAddr *addr, PRIntervalTime timeout);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_Bind
+ * DESCRIPTION:
+ *    Bind an address to a socket.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       Points to a PRFileDesc object representing a socket.
+ *     PRNetAddr *addr
+ *       Specifies the address to which the socket will be bound.
+ * OUTPUTS:
+ *     None
+ * RETURN: PRStatus
+ *     Upon successful binding of an address to a socket, PR_Bind
+ *     returns PR_SUCCESS.  Otherwise, it returns PR_FAILURE.  Further
+ *     failure information can be obtained by calling PR_GetError().
+ **************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_Bind(PRFileDesc *fd, const PRNetAddr *addr);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_Listen
+ * DESCRIPTION:
+ *    Listen for connections on a socket.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       Points to a PRFileDesc object representing a socket that will be
+ *       used to listen for new connections.
+ *     PRIntn backlog
+ *       Specifies the maximum length of the queue of pending connections.
+ * OUTPUTS:
+ *     None
+ * RETURN: PRStatus
+ *     Upon successful completion of listen request, PR_Listen
+ *     returns PR_SUCCESS.  Otherwise, it returns PR_FAILURE.  Further
+ *     failure information can be obtained by calling PR_GetError().
+ **************************************************************************
+ */
+
+NSPR_API(PRStatus) PR_Listen(PRFileDesc *fd, PRIntn backlog);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_Shutdown
+ * DESCRIPTION:
+ *    Shut down part of a full-duplex connection on a socket.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       Points to a PRFileDesc object representing a connected socket.
+ *     PRIntn how
+ *       Specifies the kind of disallowed operations on the socket.
+ *           PR_SHUTDOWN_RCV - Further receives will be disallowed
+ *           PR_SHUTDOWN_SEND - Further sends will be disallowed
+ *           PR_SHUTDOWN_BOTH - Further sends and receives will be disallowed
+ * OUTPUTS:
+ *     None
+ * RETURN: PRStatus
+ *     Upon successful completion of shutdown request, PR_Shutdown
+ *     returns PR_SUCCESS.  Otherwise, it returns PR_FAILURE.  Further
+ *     failure information can be obtained by calling PR_GetError().
+ **************************************************************************
+ */
+
+typedef enum PRShutdownHow
+{
+    PR_SHUTDOWN_RCV = 0,      /* disallow further receives */
+    PR_SHUTDOWN_SEND = 1,     /* disallow further sends */
+    PR_SHUTDOWN_BOTH = 2      /* disallow further receives and sends */
+} PRShutdownHow;
+
+NSPR_API(PRStatus)    PR_Shutdown(PRFileDesc *fd, PRShutdownHow how);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_Recv
+ * DESCRIPTION:
+ *    Receive a specified number of bytes from a connected socket.
+ *     The operation will block until some positive number of bytes are
+ *     transferred, a time out has occurred, or there is an error.
+ *     No more than 'amount' bytes will be transferred.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       points to a PRFileDesc object representing a socket.
+ *     void *buf
+ *       pointer to a buffer to hold the data received.
+ *     PRInt32 amount
+ *       the size of 'buf' (in bytes)
+ *     PRIntn flags
+ *       must be zero or PR_MSG_PEEK.
+ *     PRIntervalTime timeout
+ *       Time limit for completion of the receive operation.
+ * OUTPUTS:
+ *     None
+ * RETURN: PRInt32
+ *         a positive number indicates the number of bytes actually received.
+ *         0 means the network connection is closed.
+ *         -1 indicates a failure. The reason for the failure is obtained
+ *         by calling PR_GetError().
+ **************************************************************************
+ */
+
+#define PR_MSG_PEEK 0x2
+
+NSPR_API(PRInt32)    PR_Recv(PRFileDesc *fd, void *buf, PRInt32 amount,
+                             PRIntn flags, PRIntervalTime timeout);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_Send
+ * DESCRIPTION:
+ *    Send a specified number of bytes from a connected socket.
+ *     The operation will block until all bytes are
+ *     processed, a time out has occurred, or there is an error.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       points to a PRFileDesc object representing a socket.
+ *     void *buf
+ *       pointer to a buffer from where the data is sent.
+ *     PRInt32 amount
+ *       the size of 'buf' (in bytes)
+ *     PRIntn flags
+ *        (OBSOLETE - must always be zero)
+ *     PRIntervalTime timeout
+ *       Time limit for completion of the send operation.
+ * OUTPUTS:
+ *     None
+ * RETURN: PRInt32
+ *     A positive number indicates the number of bytes successfully processed.
+ *     This number must always equal 'amount'. A -1 is an indication that the
+ *     operation failed. The reason for the failure is obtained by calling
+ *     PR_GetError().
+ **************************************************************************
+ */
+
+NSPR_API(PRInt32)    PR_Send(PRFileDesc *fd, const void *buf, PRInt32 amount,
+                             PRIntn flags, PRIntervalTime timeout);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_RecvFrom
+ * DESCRIPTION:
+ *     Receive up to a specified number of bytes from socket which may
+ *     or may not be connected.
+ *     The operation will block until one or more bytes are
+ *     transferred, a time out has occurred, or there is an error.
+ *     No more than 'amount' bytes will be transferred.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       points to a PRFileDesc object representing a socket.
+ *     void *buf
+ *       pointer to a buffer to hold the data received.
+ *     PRInt32 amount
+ *       the size of 'buf' (in bytes)
+ *     PRIntn flags
+ *        (OBSOLETE - must always be zero)
+ *     PRNetAddr *addr
+ *       Specifies the address of the sending peer. It may be NULL.
+ *     PRIntervalTime timeout
+ *       Time limit for completion of the receive operation.
+ * OUTPUTS:
+ *     None
+ * RETURN: PRInt32
+ *         a positive number indicates the number of bytes actually received.
+ *         0 means the network connection is closed.
+ *         -1 indicates a failure. The reason for the failure is obtained
+ *         by calling PR_GetError().
+ **************************************************************************
+ */
+
+NSPR_API(PRInt32) PR_RecvFrom(
+    PRFileDesc *fd, void *buf, PRInt32 amount, PRIntn flags,
+    PRNetAddr *addr, PRIntervalTime timeout);
+
+/*
+ *************************************************************************
+ * FUNCTION: PR_SendTo
+ * DESCRIPTION:
+ *    Send a specified number of bytes from an unconnected socket.
+ *    The operation will block until all bytes are
+ *    sent, a time out has occurred, or there is an error.
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       points to a PRFileDesc object representing an unconnected socket.
+ *     void *buf
+ *       pointer to a buffer from where the data is sent.
+ *     PRInt32 amount
+ *       the size of 'buf' (in bytes)
+ *     PRIntn flags
+ *        (OBSOLETE - must always be zero)
+ *     PRNetAddr *addr
+ *       Specifies the address of the peer.
+.*     PRIntervalTime timeout
+ *       Time limit for completion of the send operation.
+ * OUTPUTS:
+ *     None
+ * RETURN: PRInt32
+ *     A positive number indicates the number of bytes successfully sent.
+ *     -1 indicates a failure. The reason for the failure is obtained
+ *     by calling PR_GetError().
+ **************************************************************************
+ */
+
+NSPR_API(PRInt32) PR_SendTo(
+    PRFileDesc *fd, const void *buf, PRInt32 amount, PRIntn flags,
+    const PRNetAddr *addr, PRIntervalTime timeout);
+
+/*
+*************************************************************************
+** FUNCTION: PR_TransmitFile
+** DESCRIPTION:
+**    Transmitfile sends a complete file (sourceFile) across a socket
+**    (networkSocket).  If headers is non-NULL, the headers will be sent across
+**    the socket prior to sending the file.
+**
+**    Optionally, the PR_TRANSMITFILE_CLOSE_SOCKET flag may be passed to
+**    transmitfile.  This flag specifies that transmitfile should close the
+**    socket after sending the data.
+**
+** INPUTS:
+**    PRFileDesc *networkSocket
+**        The socket to send data over
+**    PRFileDesc *sourceFile
+**        The file to send
+**    const void *headers
+**        A pointer to headers to be sent before sending data
+**    PRInt32       hlen
+**        length of header buffers in bytes.
+**    PRTransmitFileFlags       flags
+**        If the flags indicate that the connection should be closed,
+**        it will be done immediately after transferring the file, unless
+**        the operation is unsuccessful.
+.*     PRIntervalTime timeout
+ *        Time limit for completion of the transmit operation.
+**
+** RETURNS:
+**    Returns the number of bytes written or -1 if the operation failed.
+**    If an error occurs while sending the file, the PR_TRANSMITFILE_CLOSE_
+**    SOCKET flag is ignored. The reason for the failure is obtained
+**    by calling PR_GetError().
+**************************************************************************
+*/
+
+NSPR_API(PRInt32) PR_TransmitFile(
+    PRFileDesc *networkSocket, PRFileDesc *sourceFile,
+    const void *headers, PRInt32 hlen, PRTransmitFileFlags flags,
+    PRIntervalTime timeout);
+
+/*
+*************************************************************************
+** FUNCTION: PR_SendFile
+** DESCRIPTION:
+**    PR_SendFile sends data from a file (sendData->fd) across a socket
+**    (networkSocket).  If specified, a header and/or trailer buffer are sent
+**    before and after the file, respectively. The file offset, number of bytes
+**    of file data to send, the header and trailer buffers are specified in the
+**    sendData argument.
+**
+**    Optionally, if the PR_TRANSMITFILE_CLOSE_SOCKET flag is passed, the
+**    socket is closed after successfully sending the data.
+**
+** INPUTS:
+**    PRFileDesc *networkSocket
+**        The socket to send data over
+**    PRSendFileData *sendData
+**        Contains the FD, file offset and length, header and trailer
+**        buffer specifications.
+**    PRTransmitFileFlags       flags
+**        If the flags indicate that the connection should be closed,
+**        it will be done immediately after transferring the file, unless
+**        the operation is unsuccessful.
+.*     PRIntervalTime timeout
+ *        Time limit for completion of the send operation.
+**
+** RETURNS:
+**    Returns the number of bytes written or -1 if the operation failed.
+**    If an error occurs while sending the file, the PR_TRANSMITFILE_CLOSE_
+**    SOCKET flag is ignored. The reason for the failure is obtained
+**    by calling PR_GetError().
+**************************************************************************
+*/
+
+struct PRSendFileData {
+    PRFileDesc  *fd;            /* file to send                         */
+    PRUint32    file_offset;    /* file offset                          */
+    PRSize      file_nbytes;    /* number of bytes of file data to send */
+    /* if 0, send data from file_offset to  */
+    /* end-of-file.                         */
+    const void  *header;        /* header buffer                        */
+    PRInt32     hlen;           /* header len                           */
+    const void  *trailer;       /* trailer buffer                       */
+    PRInt32     tlen;           /* trailer len                          */
+};
+
+
+NSPR_API(PRInt32) PR_SendFile(
+    PRFileDesc *networkSocket, PRSendFileData *sendData,
+    PRTransmitFileFlags flags, PRIntervalTime timeout);
+
+/*
+*************************************************************************
+** FUNCTION: PR_AcceptRead
+** DESCRIPTION:
+**    AcceptRead accepts a new connection, returns the newly created
+**    socket's descriptor and also returns the connecting peer's address.
+**    AcceptRead, as its name suggests, also receives the first block of data
+**    sent by the peer.
+**
+** INPUTS:
+**    PRFileDesc *listenSock
+**        A socket descriptor that has been called with the PR_Listen()
+**        function, also known as the rendezvous socket.
+**    void *buf
+**        A pointer to a buffer to receive data sent by the client.  This
+**        buffer must be large enough to receive <amount> bytes of data
+**        and two PRNetAddr structures, plus an extra 32 bytes. See:
+**        PR_ACCEPT_READ_BUF_OVERHEAD.
+**    PRInt32 amount
+**        The number of bytes of client data to receive.  Does not include
+**        the size of the PRNetAddr structures.  If 0, no data will be read
+**        from the client.
+**    PRIntervalTime timeout
+**        The timeout interval only applies to the read portion of the
+**        operation.  PR_AcceptRead will block indefinitely until the
+**        connection is accepted; the read will timeout after the timeout
+**        interval elapses.
+** OUTPUTS:
+**    PRFileDesc **acceptedSock
+**        The file descriptor for the newly connected socket.  This parameter
+**        will only be valid if the function return does not indicate failure.
+**    PRNetAddr  **peerAddr,
+**        The address of the remote socket.  This parameter will only be
+**        valid if the function return does not indicate failure.  The
+**        returned address is not guaranteed to be properly aligned.
+**
+** RETURNS:
+**     The number of bytes read from the client or -1 on failure.  The reason
+**     for the failure is obtained by calling PR_GetError().
+**************************************************************************
+**/
+/* define buffer overhead constant. Add this value to the user's
+** data length when allocating a buffer to accept data.
+**    Example:
+**    #define USER_DATA_SIZE 10
+**    char buf[USER_DATA_SIZE + PR_ACCEPT_READ_BUF_OVERHEAD];
+**    bytesRead = PR_AcceptRead( s, fd, &a, &p, USER_DATA_SIZE, ...);
+*/
+#define PR_ACCEPT_READ_BUF_OVERHEAD (32+(2*sizeof(PRNetAddr)))
+
+NSPR_API(PRInt32) PR_AcceptRead(
+    PRFileDesc *listenSock, PRFileDesc **acceptedSock,
+    PRNetAddr **peerAddr, void *buf, PRInt32 amount, PRIntervalTime timeout);
+
+/*
+*************************************************************************
+** FUNCTION: PR_NewTCPSocketPair
+** DESCRIPTION:
+**    Create a new TCP socket pair. The returned descriptors can be used
+**    interchangeably; they are interconnected full-duplex descriptors: data
+**    written to one can be read from the other and vice-versa.
+**
+** INPUTS:
+**    None
+** OUTPUTS:
+**    PRFileDesc *fds[2]
+**        The file descriptor pair for the newly created TCP sockets.
+** RETURN: PRStatus
+**     Upon successful completion of TCP socket pair, PR_NewTCPSocketPair
+**     returns PR_SUCCESS.  Otherwise, it returns PR_FAILURE.  Further
+**     failure information can be obtained by calling PR_GetError().
+** XXX can we implement this on windoze and mac?
+**************************************************************************
+**/
+NSPR_API(PRStatus) PR_NewTCPSocketPair(PRFileDesc *fds[2]);
+
+/*
+*************************************************************************
+** FUNCTION: PR_GetSockName
+** DESCRIPTION:
+**    Get socket name.  Return the network address for this socket.
+**
+** INPUTS:
+**     PRFileDesc *fd
+**       Points to a PRFileDesc object representing the socket.
+** OUTPUTS:
+**     PRNetAddr *addr
+**       Returns the address of the socket in its own communication space.
+** RETURN: PRStatus
+**     Upon successful completion, PR_GetSockName returns PR_SUCCESS.
+**     Otherwise, it returns PR_FAILURE.  Further failure information can
+**     be obtained by calling PR_GetError().
+**************************************************************************
+**/
+NSPR_API(PRStatus)  PR_GetSockName(PRFileDesc *fd, PRNetAddr *addr);
+
+/*
+*************************************************************************
+** FUNCTION: PR_GetPeerName
+** DESCRIPTION:
+**    Get name of the connected peer.  Return the network address for the
+**    connected peer socket.
+**
+** INPUTS:
+**     PRFileDesc *fd
+**       Points to a PRFileDesc object representing the connected peer.
+** OUTPUTS:
+**     PRNetAddr *addr
+**       Returns the address of the connected peer in its own communication
+**       space.
+** RETURN: PRStatus
+**     Upon successful completion, PR_GetPeerName returns PR_SUCCESS.
+**     Otherwise, it returns PR_FAILURE.  Further failure information can
+**     be obtained by calling PR_GetError().
+**************************************************************************
+**/
+NSPR_API(PRStatus)  PR_GetPeerName(PRFileDesc *fd, PRNetAddr *addr);
+
+NSPR_API(PRStatus)  PR_GetSocketOption(
+    PRFileDesc *fd, PRSocketOptionData *data);
+
+NSPR_API(PRStatus)  PR_SetSocketOption(
+    PRFileDesc *fd, const PRSocketOptionData *data);
+
+/*
+ *********************************************************************
+ *
+ * File descriptor inheritance
+ *
+ *********************************************************************
+ */
+
+/*
+ ************************************************************************
+ * FUNCTION: PR_SetFDInheritable
+ * DESCRIPTION:
+ *    Set the inheritance attribute of a file descriptor.
+ *
+ * INPUTS:
+ *     PRFileDesc *fd
+ *       Points to a PRFileDesc object.
+ *     PRBool inheritable
+ *       If PR_TRUE, the file descriptor fd is set to be inheritable
+ *       by a child process.  If PR_FALSE, the file descriptor is set
+ *       to be not inheritable by a child process.
+ * RETURN: PRStatus
+ *     Upon successful completion, PR_SetFDInheritable returns PR_SUCCESS.
+ *     Otherwise, it returns PR_FAILURE.  Further failure information can
+ *     be obtained by calling PR_GetError().
+ *************************************************************************
+ */
+NSPR_API(PRStatus) PR_SetFDInheritable(
+    PRFileDesc *fd,
+    PRBool inheritable);
+
+/*
+ ************************************************************************
+ * FUNCTION: PR_GetInheritedFD
+ * DESCRIPTION:
+ *    Get an inherited file descriptor with the specified name.
+ *
+ * INPUTS:
+ *     const char *name
+ *       The name of the inherited file descriptor.
+ * RETURN: PRFileDesc *
+ *     Upon successful completion, PR_GetInheritedFD returns the
+ *     inherited file descriptor with the specified name.  Otherwise,
+ *     it returns NULL.  Further failure information can be obtained
+ *     by calling PR_GetError().
+ *************************************************************************
+ */
+NSPR_API(PRFileDesc *) PR_GetInheritedFD(const char *name);
+
+/*
+ *********************************************************************
+ *
+ * Memory-mapped files
+ *
+ *********************************************************************
+ */
+
+typedef struct PRFileMap PRFileMap;
+
+/*
+ * protection options for read and write accesses of a file mapping
+ */
+typedef enum PRFileMapProtect {
+    PR_PROT_READONLY,     /* read only */
+    PR_PROT_READWRITE,    /* readable, and write is shared */
+    PR_PROT_WRITECOPY     /* readable, and write is private (copy-on-write) */
+} PRFileMapProtect;
+
+NSPR_API(PRFileMap *) PR_CreateFileMap(
+    PRFileDesc *fd,
+    PRInt64 size,
+    PRFileMapProtect prot);
+
+/*
+ * return the alignment (in bytes) of the offset argument to PR_MemMap
+ */
+NSPR_API(PRInt32) PR_GetMemMapAlignment(void);
+
+NSPR_API(void *) PR_MemMap(
+    PRFileMap *fmap,
+    PROffset64 offset,  /* must be aligned and sized according to the
+                         * return value of PR_GetMemMapAlignment() */
+    PRUint32 len);
+
+NSPR_API(PRStatus) PR_MemUnmap(void *addr, PRUint32 len);
+
+NSPR_API(PRStatus) PR_CloseFileMap(PRFileMap *fmap);
+
+/*
+ * Synchronously flush the given memory-mapped address range of the given open
+ * file to disk. The function does not return until all modified data have
+ * been written to disk.
+ *
+ * On some platforms, the function will call PR_Sync(fd) internally if it is
+ * necessary for flushing modified data to disk synchronously.
+ */
+NSPR_API(PRStatus) PR_SyncMemMap(
+    PRFileDesc *fd,
+    void *addr,
+    PRUint32 len);
+
+/*
+ ******************************************************************
+ *
+ * Interprocess communication
+ *
+ ******************************************************************
+ */
+
+/*
+ * Creates an anonymous pipe and returns file descriptors for the
+ * read and write ends of the pipe.
+ */
+
+NSPR_API(PRStatus) PR_CreatePipe(
+    PRFileDesc **readPipe,
+    PRFileDesc **writePipe
+);
+
+/************************************************************************/
+/************** The following definitions are for poll ******************/
+/************************************************************************/
+
+struct PRPollDesc {
+    PRFileDesc* fd;
+    PRInt16 in_flags;
+    PRInt16 out_flags;
+};
+
+/*
+** Bit values for PRPollDesc.in_flags or PRPollDesc.out_flags. Binary-or
+** these together to produce the desired poll request.
+*/
+
+#if defined(_PR_POLL_BACKCOMPAT)
+
+#include <poll.h>
+#define PR_POLL_READ    POLLIN
+#define PR_POLL_WRITE   POLLOUT
+#define PR_POLL_EXCEPT  POLLPRI
+#define PR_POLL_ERR     POLLERR     /* only in out_flags */
+#define PR_POLL_NVAL    POLLNVAL    /* only in out_flags when fd is bad */
+#define PR_POLL_HUP     POLLHUP     /* only in out_flags */
+
+#else  /* _PR_POLL_BACKCOMPAT */
+
+#define PR_POLL_READ    0x1
+#define PR_POLL_WRITE   0x2
+#define PR_POLL_EXCEPT  0x4
+#define PR_POLL_ERR     0x8         /* only in out_flags */
+#define PR_POLL_NVAL    0x10        /* only in out_flags when fd is bad */
+#define PR_POLL_HUP     0x20        /* only in out_flags */
+
+#endif  /* _PR_POLL_BACKCOMPAT */
+
+/*
+*************************************************************************
+** FUNCTION:    PR_Poll
+** DESCRIPTION:
+**
+** The call returns as soon as I/O is ready on one or more of the underlying
+** socket objects. A count of the number of ready descriptors is
+** returned unless a timeout occurs in which case zero is returned.
+**
+** PRPollDesc.fd should be set to a pointer to a PRFileDesc object
+** representing a socket. This field can be set to NULL to indicate to
+** PR_Poll that this PRFileDesc object should be ignored.
+** PRPollDesc.in_flags should be set to the desired request
+** (read/write/except or some combination). Upon successful return from
+** this call PRPollDesc.out_flags will be set to indicate what kind of
+** i/o can be performed on the respective descriptor. PR_Poll() uses the
+** out_flags fields as scratch variables during the call. If PR_Poll()
+** returns 0 or -1, the out_flags fields do not contain meaningful values
+** and must not be used.
+**
+** INPUTS:
+**      PRPollDesc *pds         A pointer to an array of PRPollDesc
+**
+**      PRIntn npds             The number of elements in the array
+**                              If this argument is zero PR_Poll is
+**                              equivalent to a PR_Sleep(timeout).
+**
+**      PRIntervalTime timeout  Amount of time the call will block waiting
+**                              for I/O to become ready. If this time expires
+**                              w/o any I/O becoming ready, the result will
+**                              be zero.
+**
+** OUTPUTS:    None
+** RETURN:
+**      PRInt32                 Number of PRPollDesc's with events or zero
+**                              if the function timed out or -1 on failure.
+**                              The reason for the failure is obtained by
+**                              calling PR_GetError().
+**************************************************************************
+*/
+NSPR_API(PRInt32) PR_Poll(
+    PRPollDesc *pds, PRIntn npds, PRIntervalTime timeout);
+
+/*
+**************************************************************************
+**
+** Pollable events
+**
+** A pollable event is a special kind of file descriptor.
+** The only I/O operation you can perform on a pollable event
+** is to poll it with the PR_POLL_READ flag.  You can't
+** read from or write to a pollable event.
+**
+** The purpose of a pollable event is to combine event waiting
+** with I/O waiting in a single PR_Poll call.  Pollable events
+** are implemented using a pipe or a pair of TCP sockets
+** connected via the loopback address, therefore setting and
+** waiting for pollable events are expensive operating system
+** calls.  Do not use pollable events for general thread
+** synchronization. Use condition variables instead.
+**
+** A pollable event has two states: set and unset.  Events
+** are not queued, so there is no notion of an event count.
+** A pollable event is either set or unset.
+**
+** A new pollable event is created by a PR_NewPollableEvent
+** call and is initially in the unset state.
+**
+** PR_WaitForPollableEvent blocks the calling thread until
+** the pollable event is set, and then it atomically unsets
+** the pollable event before it returns.
+**
+** To set a pollable event, call PR_SetPollableEvent.
+**
+** One can call PR_Poll with the PR_POLL_READ flag on a pollable
+** event.  When the pollable event is set, PR_Poll returns with
+** the PR_POLL_READ flag set in the out_flags.
+**
+** To close a pollable event, call PR_DestroyPollableEvent
+** (not PR_Close).
+**
+**************************************************************************
+*/
+
+NSPR_API(PRFileDesc *) PR_NewPollableEvent(void);
+
+NSPR_API(PRStatus) PR_DestroyPollableEvent(PRFileDesc *event);
+
+NSPR_API(PRStatus) PR_SetPollableEvent(PRFileDesc *event);
+
+NSPR_API(PRStatus) PR_WaitForPollableEvent(PRFileDesc *event);
+
+PR_END_EXTERN_C
+
+#endif /* prio_h___ */