From ea648e70a989cca190cd7403fe892fd2dcc290b4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 5 May 2024 20:37:14 +0200 Subject: Adding upstream version 1:9.11.5.P4+dfsg. Signed-off-by: Daniel Baumann --- lib/lwres/man/lwres_gethostent.docbook | 433 +++++++++++++++++++++++++++++++++ 1 file changed, 433 insertions(+) create mode 100644 lib/lwres/man/lwres_gethostent.docbook (limited to 'lib/lwres/man/lwres_gethostent.docbook') diff --git a/lib/lwres/man/lwres_gethostent.docbook b/lib/lwres/man/lwres_gethostent.docbook new file mode 100644 index 0000000..f11ee07 --- /dev/null +++ b/lib/lwres/man/lwres_gethostent.docbook @@ -0,0 +1,433 @@ +]> + + + + + + 2007-06-18 + + + ISC + Internet Systems Consortium, Inc. + + + + lwres_gethostent + 3 + BIND9 + + + + + 2001 + 2004 + 2005 + 2007 + 2014 + 2015 + 2016 + 2018 + 2019 + Internet Systems Consortium, Inc. ("ISC") + + + + + lwres_gethostbyname + lwres_gethostbyname2 + lwres_gethostbyaddr + lwres_gethostent + lwres_sethostent + lwres_endhostent + lwres_gethostbyname_r + lwres_gethostbyaddr_r + lwres_gethostent_r + lwres_sethostent_r + lwres_endhostent_r + lightweight resolver get network host entry + + + +#include <lwres/netdb.h> + + +struct hostent * +lwres_gethostbyname + const char *name + + + +struct hostent * +lwres_gethostbyname2 + const char *name + int af + + + +struct hostent * +lwres_gethostbyaddr + const char *addr + int len + int type + + + +struct hostent * +lwres_gethostent + void + + + +void +lwres_sethostent + int stayopen + + + +void +lwres_endhostent + void + + + +struct hostent * +lwres_gethostbyname_r + const char *name + struct hostent *resbuf + char *buf + int buflen + int *error + + + +struct hostent * +lwres_gethostbyaddr_r + const char *addr + int len + int type + struct hostent *resbuf + char *buf + int buflen + int *error + + + +struct hostent * +lwres_gethostent_r + struct hostent *resbuf + char *buf + int buflen + int *error + + + +void +lwres_sethostent_r + int stayopen + + + +void +lwres_endhostent_r + void + + + + + DESCRIPTION + + + These functions provide hostname-to-address and + address-to-hostname lookups by means of the lightweight resolver. + They are similar to the standard + + gethostent3 + + functions provided by most operating systems. + They use a + struct hostent + which is usually defined in + <namedb.h>. + + +struct hostent { + char *h_name; /* official name of host */ + char **h_aliases; /* alias list */ + int h_addrtype; /* host address type */ + int h_length; /* length of address */ + char **h_addr_list; /* list of addresses from name server */ +}; +#define h_addr h_addr_list[0] /* address, for backward compatibility */ + + + + The members of this structure are: + + + h_name + + + The official (canonical) name of the host. + + + + + h_aliases + + + A NULL-terminated array of alternate names (nicknames) for the + host. + + + + + h_addrtype + + + The type of address being returned — + PF_INET + or + PF_INET6. + + + + + h_length + + + The length of the address in bytes. + + + + + h_addr_list + + + A NULL + terminated array of network addresses for the host. + Host addresses are returned in network byte order. + + + + + + + For backward compatibility with very old software, + h_addr + is the first address in + h_addr_list. + + lwres_gethostent(), + lwres_sethostent(), + lwres_endhostent(), + lwres_gethostent_r(), + lwres_sethostent_r() + and + lwres_endhostent_r() + provide iteration over the known host entries on systems that + provide such functionality through facilities like + /etc/hosts + or NIS. The lightweight resolver does not currently implement + these functions; it only provides them as stub functions that always + return failure. + + + lwres_gethostbyname() + and lwres_gethostbyname2() look up the + hostname name. + lwres_gethostbyname() always looks for an + IPv4 address while lwres_gethostbyname2() + looks for an address of protocol family + af: either PF_INET or + PF_INET6 — IPv4 or IPV6 addresses + respectively. Successful calls of the functions return a + struct hostentfor the name that was looked up. + NULL is returned if the lookups by + lwres_gethostbyname() or + lwres_gethostbyname2() fail. + + + + Reverse lookups of addresses are performed by + lwres_gethostbyaddr(). + addr is an address of length + len bytes and protocol family + type — PF_INET or + PF_INET6. + lwres_gethostbyname_r() is a + thread-safe function + for forward lookups. If an error occurs, an error code is returned in + *error. + resbuf is a pointer to a + struct hostent which is initialised by a successful call to + lwres_gethostbyname_r(). + buf is a buffer of length + len bytes which is used to store the + h_name, h_aliases, and + h_addr_list elements of the + struct hostent returned in resbuf. + Successful calls to lwres_gethostbyname_r() + return resbuf, + which is a pointer to the struct hostent it created. + + + lwres_gethostbyaddr_r() + is a thread-safe function + that performs a reverse lookup of address addr + which is len bytes long and is of + protocol + family type — PF_INET or + PF_INET6. If an error occurs, the error code is returned + in *error. The other function + parameters are + identical to those in lwres_gethostbyname_r(). + resbuf is a pointer to a + struct hostent which is initialised by a successful call to + lwres_gethostbyaddr_r(). + buf is a buffer of length + len bytes which is used to store the + h_name, h_aliases, and + h_addr_list elements of the + struct hostent returned in resbuf. + Successful calls to lwres_gethostbyaddr_r() return + resbuf, which is a pointer to the + struct hostent() it created. + + + + + RETURN VALUES + + + The functions + lwres_gethostbyname(), + lwres_gethostbyname2(), + lwres_gethostbyaddr(), + and + lwres_gethostent() + return NULL to indicate an error. In this case the global variable + lwres_h_errno + will contain one of the following error codes defined in + <lwres/netdb.h>: + + + + HOST_NOT_FOUND + + + The host or address was not found. + + + + + TRY_AGAIN + + + A recoverable error occurred, e.g., a timeout. + Retrying the lookup may succeed. + + + + + NO_RECOVERY + + + A non-recoverable error occurred. + + + + + NO_DATA + + + The name exists, but has no address information + associated with it (or vice versa in the case + of a reverse lookup). The code NO_ADDRESS + is accepted as a synonym for NO_DATA for backwards + compatibility. + + + + + + + + lwres_hstrerror3 + + translates these error codes to suitable error messages. + + + lwres_gethostent() + and lwres_gethostent_r() + always return NULL. + + + + Successful calls to lwres_gethostbyname_r() and + lwres_gethostbyaddr_r() return + resbuf, a pointer to the + struct hostent that was initialised by these functions. They return + NULL if the lookups fail or if buf + was too small to hold the list of addresses and names referenced by + the h_name, h_aliases, and + h_addr_list elements of the + struct hostent. + If buf was too small, both + lwres_gethostbyname_r() and + lwres_gethostbyaddr_r() set the global + variable + errno to ERANGE. + + + + SEE ALSO + + + gethostent3 + , + + + lwres_getipnode3 + , + + + lwres_hstrerror3 + + + + + BUGS + + lwres_gethostbyname(), + lwres_gethostbyname2(), + lwres_gethostbyaddr() + and + lwres_endhostent() + are not thread safe; they return pointers to static data and + provide error codes through a global variable. + Thread-safe versions for name and address lookup are provided by + lwres_gethostbyname_r(), + and + lwres_gethostbyaddr_r() + respectively. + + + The resolver daemon does not currently support any non-DNS + name services such as + /etc/hosts + or + NIS, + consequently the above functions don't, either. + + + -- cgit v1.2.3