path: root/templates/man2/select_tut.2.pot

# SOME DESCRIPTIVE TITLE
# Copyright (C) YEAR Free Software Foundation, Inc.
# This file is distributed under the same license as the PACKAGE package.
# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
#
#, fuzzy
msgid ""
msgstr ""
"Project-Id-Version: PACKAGE VERSION\n"
"POT-Creation-Date: 2024-03-01 17:07+0100\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
"Language: \n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"

#. type: TH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "SELECT_TUT"
msgstr ""

#. type: TH
#: archlinux fedora-40 fedora-rawhide mageia-cauldron
#, no-wrap
msgid "2023-10-31"
msgstr ""

#. type: TH
#: archlinux fedora-40 fedora-rawhide mageia-cauldron
#, no-wrap
msgid "Linux man-pages 6.06"
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "NAME"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid "select, pselect - synchronous I/O multiplexing"
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "LIBRARY"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid "Standard C library (I<libc>, I<-lc>)"
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "SYNOPSIS"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid "See B<select>(2)"
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "DESCRIPTION"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The B<select>()  and B<pselect>()  system calls are used to efficiently "
"monitor multiple file descriptors, to see if any of them is, or becomes, "
"\"ready\"; that is, to see whether I/O becomes possible, or an \"exceptional "
"condition\" has occurred on any of the file descriptors."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"This page provides background and tutorial information on the use of these "
"system calls.  For details of the arguments and semantics of B<select>()  "
"and B<pselect>(), see B<select>(2)."
msgstr ""

#. type: SS
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "Combining signal and data events"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"B<pselect>()  is useful if you are waiting for a signal as well as for file "
"descriptor(s) to become ready for I/O.  Programs that receive signals "
"normally use the signal handler only to raise a global flag.  The global "
"flag will indicate that the event must be processed in the main loop of the "
"program.  A signal will cause the B<select>()  (or B<pselect>())  call to "
"return with I<errno> set to B<EINTR>.  This behavior is essential so that "
"signals can be processed in the main loop of the program, otherwise "
"B<select>()  would block indefinitely."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Now, somewhere in the main loop will be a conditional to check the global "
"flag.  So we must ask: what if a signal arrives after the conditional, but "
"before the B<select>()  call? The answer is that B<select>()  would block "
"indefinitely, even though an event is actually pending.  This race condition "
"is solved by the B<pselect>()  call.  This call can be used to set the "
"signal mask to a set of signals that are to be received only within the "
"B<pselect>()  call.  For instance, let us say that the event in question was "
"the exit of a child process.  Before the start of the main loop, we would "
"block B<SIGCHLD> using B<sigprocmask>(2).  Our B<pselect>()  call would "
"enable B<SIGCHLD> by using an empty signal mask.  Our program would look "
"like:"
msgstr ""

#. type: Plain text
#: archlinux debian-unstable fedora-40 fedora-rawhide mageia-cauldron
#: opensuse-tumbleweed
#, no-wrap
msgid ""
"static volatile sig_atomic_t got_SIGCHLD = 0;\n"
"\\&\n"
"static void\n"
"child_sig_handler(int sig)\n"
"{\n"
"    got_SIGCHLD = 1;\n"
"}\n"
"\\&\n"
"int\n"
"main(int argc, char *argv[])\n"
"{\n"
"    sigset_t sigmask, empty_mask;\n"
"    struct sigaction sa;\n"
"    fd_set readfds, writefds, exceptfds;\n"
"    int r;\n"
"\\&\n"
"    sigemptyset(&sigmask);\n"
"    sigaddset(&sigmask, SIGCHLD);\n"
"    if (sigprocmask(SIG_BLOCK, &sigmask, NULL) == -1) {\n"
"        perror(\"sigprocmask\");\n"
"        exit(EXIT_FAILURE);\n"
"    }\n"
"\\&\n"
"    sa.sa_flags = 0;\n"
"    sa.sa_handler = child_sig_handler;\n"
"    sigemptyset(&sa.sa_mask);\n"
"    if (sigaction(SIGCHLD, &sa, NULL) == -1) {\n"
"        perror(\"sigaction\");\n"
"        exit(EXIT_FAILURE);\n"
"    }\n"
"\\&\n"
"    sigemptyset(&empty_mask);\n"
"\\&\n"
"    for (;;) {          /* main loop */\n"
"        /* Initialize readfds, writefds, and exceptfds\n"
"           before the pselect() call. (Code omitted.) */\n"
"\\&\n"
"        r = pselect(nfds, &readfds, &writefds, &exceptfds,\n"
"                    NULL, &empty_mask);\n"
"        if (r == -1 && errno != EINTR) {\n"
"            /* Handle error */\n"
"        }\n"
"\\&\n"
"        if (got_SIGCHLD) {\n"
"            got_SIGCHLD = 0;\n"
"\\&\n"
"            /* Handle signalled event here; e.g., wait() for all\n"
"               terminated children. (Code omitted.) */\n"
"        }\n"
"\\&\n"
"        /* main body of program */\n"
"    }\n"
"}\n"
msgstr ""

#. type: SS
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "Practical"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"So what is the point of B<select>()? Can't I just read and write to my file "
"descriptors whenever I want? The point of B<select>()  is that it watches "
"multiple descriptors at the same time and properly puts the process to sleep "
"if there is no activity.  UNIX programmers often find themselves in a "
"position where they have to handle I/O from more than one file descriptor "
"where the data flow may be intermittent.  If you were to merely create a "
"sequence of B<read>(2)  and B<write>(2)  calls, you would find that one of "
"your calls may block waiting for data from/to a file descriptor, while "
"another file descriptor is unused though ready for I/O.  B<select>()  "
"efficiently copes with this situation."
msgstr ""

#. type: SS
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "Select law"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Many people who try to use B<select>()  come across behavior that is "
"difficult to understand and produces nonportable or borderline results.  For "
"instance, the above program is carefully written not to block at any point, "
"even though it does not set its file descriptors to nonblocking mode.  It is "
"easy to introduce subtle errors that will remove the advantage of using "
"B<select>(), so here is a list of essentials to watch for when using "
"B<select>()."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "1."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"You should always try to use B<select>()  without a timeout.  Your program "
"should have nothing to do if there is no data available.  Code that depends "
"on timeouts is not usually portable and is difficult to debug."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "2."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The value I<nfds> must be properly calculated for efficiency as explained "
"above."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "3."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"No file descriptor must be added to any set if you do not intend to check "
"its result after the B<select>()  call, and respond appropriately.  See next "
"rule."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "4."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"After B<select>()  returns, all file descriptors in all sets should be "
"checked to see if they are ready."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "5."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The functions B<read>(2), B<recv>(2), B<write>(2), and B<send>(2)  do I<not> "
"necessarily read/write the full amount of data that you have requested.  If "
"they do read/write the full amount, it's because you have a low traffic load "
"and a fast stream.  This is not always going to be the case.  You should "
"cope with the case of your functions managing to send or receive only a "
"single byte."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "6."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Never read/write only in single bytes at a time unless you are really sure "
"that you have a small amount of data to process.  It is extremely "
"inefficient not to read/write as much data as you can buffer each time.  The "
"buffers in the example below are 1024 bytes although they could easily be "
"made larger."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "7."
msgstr ""

#.  Nonetheless, you should still cope with these errors for completeness.
#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Calls to B<read>(2), B<recv>(2), B<write>(2), B<send>(2), and B<select>()  "
"can fail with the error B<EINTR>, and calls to B<read>(2), B<recv>(2), "
"B<write>(2), and B<send>(2)  can fail with I<errno> set to B<EAGAIN> "
"(B<EWOULDBLOCK>).  These results must be properly managed (not done properly "
"above).  If your program is not going to receive any signals, then it is "
"unlikely you will get B<EINTR>.  If your program does not set nonblocking I/"
"O, you will not get B<EAGAIN>."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "8."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Never call B<read>(2), B<recv>(2), B<write>(2), or B<send>(2)  with a buffer "
"length of zero."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "9."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"If the functions B<read>(2), B<recv>(2), B<write>(2), and B<send>(2)  fail "
"with errors other than those listed in B<7.>, or one of the input functions "
"returns 0, indicating end of file, then you should I<not> pass that file "
"descriptor to B<select>()  again.  In the example below, I close the file "
"descriptor immediately, and then set it to -1 to prevent it being included "
"in a set."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "10."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The timeout value must be initialized with each new call to B<select>(), "
"since some operating systems modify the structure.  B<pselect>()  however "
"does not modify its timeout structure."
msgstr ""

#. type: TP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "11."
msgstr ""

#.  "I have heard" does not fill me with confidence, and doesn't
#.  belong in a man page, so I've commented this point out.
#.  .TP
#.  11.
#.  I have heard that the Windows socket layer does not cope with OOB data
#.  properly.
#.  It also does not cope with
#.  .BR select ()
#.  calls when no file descriptors are set at all.
#.  Having no file descriptors set is a useful
#.  way to sleep the process with subsecond precision by using the timeout.
#.  (See further on.)
#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Since B<select>()  modifies its file descriptor sets, if the call is being "
"used in a loop, then the sets must be reinitialized before each call."
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "RETURN VALUE"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid "See B<select>(2)."
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "NOTES"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Generally speaking, all operating systems that support sockets also support "
"B<select>().  B<select>()  can be used to solve many problems in a portable "
"and efficient way that naive programmers try to solve in a more complicated "
"manner using threads, forking, IPCs, signals, memory sharing, and so on."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The B<poll>(2)  system call has the same functionality as B<select>(), and "
"is somewhat more efficient when monitoring sparse file descriptor sets.  It "
"is nowadays widely available, but historically was less portable than "
"B<select>()."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The Linux-specific B<epoll>(7)  API provides an interface that is more "
"efficient than B<select>(2)  and B<poll>(2)  when monitoring large numbers "
"of file descriptors."
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "EXAMPLES"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Here is an example that better demonstrates the true utility of "
"B<select>().  The listing below is a TCP forwarding program that forwards "
"from one TCP port to another."
msgstr ""

#. type: Plain text
#: archlinux debian-unstable fedora-40 fedora-rawhide mageia-cauldron
#: opensuse-tumbleweed
#, no-wrap
msgid ""
"#include E<lt>arpa/inet.hE<gt>\n"
"#include E<lt>errno.hE<gt>\n"
"#include E<lt>netinet/in.hE<gt>\n"
"#include E<lt>signal.hE<gt>\n"
"#include E<lt>stdio.hE<gt>\n"
"#include E<lt>stdlib.hE<gt>\n"
"#include E<lt>string.hE<gt>\n"
"#include E<lt>sys/select.hE<gt>\n"
"#include E<lt>sys/socket.hE<gt>\n"
"#include E<lt>unistd.hE<gt>\n"
"\\&\n"
"static int forward_port;\n"
"\\&\n"
"#undef max\n"
"#define max(x, y) ((x) E<gt> (y) ? (x) : (y))\n"
"\\&\n"
"static int\n"
"listen_socket(int listen_port)\n"
"{\n"
"    int                 lfd;\n"
"    int                 yes;\n"
"    struct sockaddr_in  addr;\n"
"\\&\n"
"    lfd = socket(AF_INET, SOCK_STREAM, 0);\n"
"    if (lfd == -1) {\n"
"        perror(\"socket\");\n"
"        return -1;\n"
"    }\n"
"\\&\n"
"    yes = 1;\n"
"    if (setsockopt(lfd, SOL_SOCKET, SO_REUSEADDR,\n"
"                   &yes, sizeof(yes)) == -1)\n"
"    {\n"
"        perror(\"setsockopt\");\n"
"        close(lfd);\n"
"        return -1;\n"
"    }\n"
"\\&\n"
"    memset(&addr, 0, sizeof(addr));\n"
"    addr.sin_port = htons(listen_port);\n"
"    addr.sin_family = AF_INET;\n"
"    if (bind(lfd, (struct sockaddr *) &addr, sizeof(addr)) == -1) {\n"
"        perror(\"bind\");\n"
"        close(lfd);\n"
"        return -1;\n"
"    }\n"
"\\&\n"
"    printf(\"accepting connections on port %d\\en\", listen_port);\n"
"    listen(lfd, 10);\n"
"    return lfd;\n"
"}\n"
"\\&\n"
"static int\n"
"connect_socket(int connect_port, char *address)\n"
"{\n"
"    int                 cfd;\n"
"    struct sockaddr_in  addr;\n"
"\\&\n"
"    cfd = socket(AF_INET, SOCK_STREAM, 0);\n"
"    if (cfd == -1) {\n"
"        perror(\"socket\");\n"
"        return -1;\n"
"    }\n"
"\\&\n"
"    memset(&addr, 0, sizeof(addr));\n"
"    addr.sin_port = htons(connect_port);\n"
"    addr.sin_family = AF_INET;\n"
"\\&\n"
"    if (!inet_aton(address, (struct in_addr *) &addr.sin_addr.s_addr)) {\n"
"        fprintf(stderr, \"inet_aton(): bad IP address format\\en\");\n"
"        close(cfd);\n"
"        return -1;\n"
"    }\n"
"\\&\n"
"    if (connect(cfd, (struct sockaddr *) &addr, sizeof(addr)) == -1) {\n"
"        perror(\"connect()\");\n"
"        shutdown(cfd, SHUT_RDWR);\n"
"        close(cfd);\n"
"        return -1;\n"
"    }\n"
"    return cfd;\n"
"}\n"
"\\&\n"
"#define SHUT_FD1 do {                                \\e\n"
"                     if (fd1 E<gt>= 0) {                 \\e\n"
"                         shutdown(fd1, SHUT_RDWR);   \\e\n"
"                         close(fd1);                 \\e\n"
"                         fd1 = -1;                   \\e\n"
"                     }                               \\e\n"
"                 } while (0)\n"
"\\&\n"
"#define SHUT_FD2 do {                                \\e\n"
"                     if (fd2 E<gt>= 0) {                 \\e\n"
"                         shutdown(fd2, SHUT_RDWR);   \\e\n"
"                         close(fd2);                 \\e\n"
"                         fd2 = -1;                   \\e\n"
"                     }                               \\e\n"
"                 } while (0)\n"
"\\&\n"
"#define BUF_SIZE 1024\n"
"\\&\n"
"int\n"
"main(int argc, char *argv[])\n"
"{\n"
"    int      h;\n"
"    int      ready, nfds;\n"
"    int      fd1 = -1, fd2 = -1;\n"
"    int      buf1_avail = 0, buf1_written = 0;\n"
"    int      buf2_avail = 0, buf2_written = 0;\n"
"    char     buf1[BUF_SIZE], buf2[BUF_SIZE];\n"
"    fd_set   readfds, writefds, exceptfds;\n"
"    ssize_t  nbytes;\n"
"\\&\n"
"    if (argc != 4) {\n"
"        fprintf(stderr, \"Usage\\en\\etfwd E<lt>listen-portE<gt> \"\n"
"                \"E<lt>forward-to-portE<gt> E<lt>forward-to-ip-addressE<gt>\\en\");\n"
"        exit(EXIT_FAILURE);\n"
"    }\n"
"\\&\n"
"    signal(SIGPIPE, SIG_IGN);\n"
"\\&\n"
"    forward_port = atoi(argv[2]);\n"
"\\&\n"
"    h = listen_socket(atoi(argv[1]));\n"
"    if (h == -1)\n"
"        exit(EXIT_FAILURE);\n"
"\\&\n"
"    for (;;) {\n"
"        nfds = 0;\n"
"\\&\n"
"        FD_ZERO(&readfds);\n"
"        FD_ZERO(&writefds);\n"
"        FD_ZERO(&exceptfds);\n"
"        FD_SET(h, &readfds);\n"
"        nfds = max(nfds, h);\n"
"\\&\n"
"        if (fd1 E<gt> 0 && buf1_avail E<lt> BUF_SIZE)\n"
"            FD_SET(fd1, &readfds);\n"
"            /* Note: nfds is updated below, when fd1 is added to\n"
"               exceptfds. */\n"
"        if (fd2 E<gt> 0 && buf2_avail E<lt> BUF_SIZE)\n"
"            FD_SET(fd2, &readfds);\n"
"\\&\n"
"        if (fd1 E<gt> 0 && buf2_avail - buf2_written E<gt> 0)\n"
"            FD_SET(fd1, &writefds);\n"
"        if (fd2 E<gt> 0 && buf1_avail - buf1_written E<gt> 0)\n"
"            FD_SET(fd2, &writefds);\n"
"\\&\n"
"        if (fd1 E<gt> 0) {\n"
"            FD_SET(fd1, &exceptfds);\n"
"            nfds = max(nfds, fd1);\n"
"        }\n"
"        if (fd2 E<gt> 0) {\n"
"            FD_SET(fd2, &exceptfds);\n"
"            nfds = max(nfds, fd2);\n"
"        }\n"
"\\&\n"
"        ready = select(nfds + 1, &readfds, &writefds, &exceptfds, NULL);\n"
"\\&\n"
"        if (ready == -1 && errno == EINTR)\n"
"            continue;\n"
"\\&\n"
"        if (ready == -1) {\n"
"            perror(\"select()\");\n"
"            exit(EXIT_FAILURE);\n"
"        }\n"
"\\&\n"
"        if (FD_ISSET(h, &readfds)) {\n"
"            socklen_t addrlen;\n"
"            struct sockaddr_in client_addr;\n"
"            int fd;\n"
"\\&\n"
"            addrlen = sizeof(client_addr);\n"
"            memset(&client_addr, 0, addrlen);\n"
"            fd = accept(h, (struct sockaddr *) &client_addr, &addrlen);\n"
"            if (fd == -1) {\n"
"                perror(\"accept()\");\n"
"            } else {\n"
"                SHUT_FD1;\n"
"                SHUT_FD2;\n"
"                buf1_avail = buf1_written = 0;\n"
"                buf2_avail = buf2_written = 0;\n"
"                fd1 = fd;\n"
"                fd2 = connect_socket(forward_port, argv[3]);\n"
"                if (fd2 == -1)\n"
"                    SHUT_FD1;\n"
"                else\n"
"                    printf(\"connect from %s\\en\",\n"
"                           inet_ntoa(client_addr.sin_addr));\n"
"\\&\n"
"                /* Skip any events on the old, closed file\n"
"                   descriptors. */\n"
"\\&\n"
"                continue;\n"
"            }\n"
"        }\n"
"\\&\n"
"        /* NB: read OOB data before normal reads. */\n"
"\\&\n"
"        if (fd1 E<gt> 0 && FD_ISSET(fd1, &exceptfds)) {\n"
"            char c;\n"
"\\&\n"
"            nbytes = recv(fd1, &c, 1, MSG_OOB);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD1;\n"
"            else\n"
"                send(fd2, &c, 1, MSG_OOB);\n"
"        }\n"
"        if (fd2 E<gt> 0 && FD_ISSET(fd2, &exceptfds)) {\n"
"            char c;\n"
"\\&\n"
"            nbytes = recv(fd2, &c, 1, MSG_OOB);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD2;\n"
"            else\n"
"                send(fd1, &c, 1, MSG_OOB);\n"
"        }\n"
"        if (fd1 E<gt> 0 && FD_ISSET(fd1, &readfds)) {\n"
"            nbytes = read(fd1, buf1 + buf1_avail,\n"
"                          BUF_SIZE - buf1_avail);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD1;\n"
"            else\n"
"                buf1_avail += nbytes;\n"
"        }\n"
"        if (fd2 E<gt> 0 && FD_ISSET(fd2, &readfds)) {\n"
"            nbytes = read(fd2, buf2 + buf2_avail,\n"
"                          BUF_SIZE - buf2_avail);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD2;\n"
"            else\n"
"                buf2_avail += nbytes;\n"
"        }\n"
"        if (fd1 E<gt> 0 && FD_ISSET(fd1, &writefds) && buf2_avail E<gt> 0) {\n"
"            nbytes = write(fd1, buf2 + buf2_written,\n"
"                           buf2_avail - buf2_written);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD1;\n"
"            else\n"
"                buf2_written += nbytes;\n"
"        }\n"
"        if (fd2 E<gt> 0 && FD_ISSET(fd2, &writefds) && buf1_avail E<gt> 0) {\n"
"            nbytes = write(fd2, buf1 + buf1_written,\n"
"                           buf1_avail - buf1_written);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD2;\n"
"            else\n"
"                buf1_written += nbytes;\n"
"        }\n"
"\\&\n"
"        /* Check if write data has caught read data. */\n"
"\\&\n"
"        if (buf1_written == buf1_avail)\n"
"            buf1_written = buf1_avail = 0;\n"
"        if (buf2_written == buf2_avail)\n"
"            buf2_written = buf2_avail = 0;\n"
"\\&\n"
"        /* One side has closed the connection, keep\n"
"           writing to the other side until empty. */\n"
"\\&\n"
"        if (fd1 E<lt> 0 && buf1_avail - buf1_written == 0)\n"
"            SHUT_FD2;\n"
"        if (fd2 E<lt> 0 && buf2_avail - buf2_written == 0)\n"
"            SHUT_FD1;\n"
"    }\n"
"    exit(EXIT_SUCCESS);\n"
"}\n"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The above program properly forwards most kinds of TCP connections including "
"OOB signal data transmitted by B<telnet> servers.  It handles the tricky "
"problem of having data flow in both directions simultaneously.  You might "
"think it more efficient to use a B<fork>(2)  call and devote a thread to "
"each stream.  This becomes more tricky than you might suspect.  Another idea "
"is to set nonblocking I/O using B<fcntl>(2).  This also has its problems "
"because you end up using inefficient timeouts."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The program does not handle more than one simultaneous connection at a time, "
"although it could easily be extended to do this with a linked list of "
"buffers\\[em]one for each connection.  At the moment, new connections cause "
"the current connection to be dropped."
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "SEE ALSO"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"B<accept>(2), B<connect>(2), B<poll>(2), B<read>(2), B<recv>(2), "
"B<select>(2), B<send>(2), B<sigprocmask>(2), B<write>(2), B<epoll>(7)"
msgstr ""

#. type: TH
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "2023-02-05"
msgstr ""

#. type: TH
#: debian-bookworm
#, no-wrap
msgid "Linux man-pages 6.03"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "static volatile sig_atomic_t got_SIGCHLD = 0;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"static void\n"
"child_sig_handler(int sig)\n"
"{\n"
"    got_SIGCHLD = 1;\n"
"}\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"int\n"
"main(int argc, char *argv[])\n"
"{\n"
"    sigset_t sigmask, empty_mask;\n"
"    struct sigaction sa;\n"
"    fd_set readfds, writefds, exceptfds;\n"
"    int r;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    sigemptyset(&sigmask);\n"
"    sigaddset(&sigmask, SIGCHLD);\n"
"    if (sigprocmask(SIG_BLOCK, &sigmask, NULL) == -1) {\n"
"        perror(\"sigprocmask\");\n"
"        exit(EXIT_FAILURE);\n"
"    }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    sa.sa_flags = 0;\n"
"    sa.sa_handler = child_sig_handler;\n"
"    sigemptyset(&sa.sa_mask);\n"
"    if (sigaction(SIGCHLD, &sa, NULL) == -1) {\n"
"        perror(\"sigaction\");\n"
"        exit(EXIT_FAILURE);\n"
"    }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "    sigemptyset(&empty_mask);\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    for (;;) {          /* main loop */\n"
"        /* Initialize readfds, writefds, and exceptfds\n"
"           before the pselect() call. (Code omitted.) */\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        r = pselect(nfds, &readfds, &writefds, &exceptfds,\n"
"                    NULL, &empty_mask);\n"
"        if (r == -1 && errno != EINTR) {\n"
"            /* Handle error */\n"
"        }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (got_SIGCHLD) {\n"
"            got_SIGCHLD = 0;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"            /* Handle signalled event here; e.g., wait() for all\n"
"               terminated children. (Code omitted.) */\n"
"        }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        /* main body of program */\n"
"    }\n"
"}\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"#include E<lt>arpa/inet.hE<gt>\n"
"#include E<lt>errno.hE<gt>\n"
"#include E<lt>netinet/in.hE<gt>\n"
"#include E<lt>signal.hE<gt>\n"
"#include E<lt>stdio.hE<gt>\n"
"#include E<lt>stdlib.hE<gt>\n"
"#include E<lt>string.hE<gt>\n"
"#include E<lt>sys/select.hE<gt>\n"
"#include E<lt>sys/socket.hE<gt>\n"
"#include E<lt>unistd.hE<gt>\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "static int forward_port;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"#undef max\n"
"#define max(x, y) ((x) E<gt> (y) ? (x) : (y))\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"static int\n"
"listen_socket(int listen_port)\n"
"{\n"
"    int                 lfd;\n"
"    int                 yes;\n"
"    struct sockaddr_in  addr;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    lfd = socket(AF_INET, SOCK_STREAM, 0);\n"
"    if (lfd == -1) {\n"
"        perror(\"socket\");\n"
"        return -1;\n"
"    }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    yes = 1;\n"
"    if (setsockopt(lfd, SOL_SOCKET, SO_REUSEADDR,\n"
"                   &yes, sizeof(yes)) == -1)\n"
"    {\n"
"        perror(\"setsockopt\");\n"
"        close(lfd);\n"
"        return -1;\n"
"    }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    memset(&addr, 0, sizeof(addr));\n"
"    addr.sin_port = htons(listen_port);\n"
"    addr.sin_family = AF_INET;\n"
"    if (bind(lfd, (struct sockaddr *) &addr, sizeof(addr)) == -1) {\n"
"        perror(\"bind\");\n"
"        close(lfd);\n"
"        return -1;\n"
"    }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    printf(\"accepting connections on port %d\\en\", listen_port);\n"
"    listen(lfd, 10);\n"
"    return lfd;\n"
"}\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"static int\n"
"connect_socket(int connect_port, char *address)\n"
"{\n"
"    int                 cfd;\n"
"    struct sockaddr_in  addr;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    cfd = socket(AF_INET, SOCK_STREAM, 0);\n"
"    if (cfd == -1) {\n"
"        perror(\"socket\");\n"
"        return -1;\n"
"    }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    memset(&addr, 0, sizeof(addr));\n"
"    addr.sin_port = htons(connect_port);\n"
"    addr.sin_family = AF_INET;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    if (!inet_aton(address, (struct in_addr *) &addr.sin_addr.s_addr)) {\n"
"        fprintf(stderr, \"inet_aton(): bad IP address format\\en\");\n"
"        close(cfd);\n"
"        return -1;\n"
"    }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    if (connect(cfd, (struct sockaddr *) &addr, sizeof(addr)) == -1) {\n"
"        perror(\"connect()\");\n"
"        shutdown(cfd, SHUT_RDWR);\n"
"        close(cfd);\n"
"        return -1;\n"
"    }\n"
"    return cfd;\n"
"}\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"#define SHUT_FD1 do {                                \\e\n"
"                     if (fd1 E<gt>= 0) {                 \\e\n"
"                         shutdown(fd1, SHUT_RDWR);   \\e\n"
"                         close(fd1);                 \\e\n"
"                         fd1 = -1;                   \\e\n"
"                     }                               \\e\n"
"                 } while (0)\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"#define SHUT_FD2 do {                                \\e\n"
"                     if (fd2 E<gt>= 0) {                 \\e\n"
"                         shutdown(fd2, SHUT_RDWR);   \\e\n"
"                         close(fd2);                 \\e\n"
"                         fd2 = -1;                   \\e\n"
"                     }                               \\e\n"
"                 } while (0)\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "#define BUF_SIZE 1024\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"int\n"
"main(int argc, char *argv[])\n"
"{\n"
"    int      h;\n"
"    int      ready, nfds;\n"
"    int      fd1 = -1, fd2 = -1;\n"
"    int      buf1_avail = 0, buf1_written = 0;\n"
"    int      buf2_avail = 0, buf2_written = 0;\n"
"    char     buf1[BUF_SIZE], buf2[BUF_SIZE];\n"
"    fd_set   readfds, writefds, exceptfds;\n"
"    ssize_t  nbytes;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    if (argc != 4) {\n"
"        fprintf(stderr, \"Usage\\en\\etfwd E<lt>listen-portE<gt> \"\n"
"                \"E<lt>forward-to-portE<gt> E<lt>forward-to-ip-addressE<gt>\\en\");\n"
"        exit(EXIT_FAILURE);\n"
"    }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "    signal(SIGPIPE, SIG_IGN);\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "    forward_port = atoi(argv[2]);\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    h = listen_socket(atoi(argv[1]));\n"
"    if (h == -1)\n"
"        exit(EXIT_FAILURE);\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"    for (;;) {\n"
"        nfds = 0;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        FD_ZERO(&readfds);\n"
"        FD_ZERO(&writefds);\n"
"        FD_ZERO(&exceptfds);\n"
"        FD_SET(h, &readfds);\n"
"        nfds = max(nfds, h);\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (fd1 E<gt> 0 && buf1_avail E<lt> BUF_SIZE)\n"
"            FD_SET(fd1, &readfds);\n"
"            /* Note: nfds is updated below, when fd1 is added to\n"
"               exceptfds. */\n"
"        if (fd2 E<gt> 0 && buf2_avail E<lt> BUF_SIZE)\n"
"            FD_SET(fd2, &readfds);\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (fd1 E<gt> 0 && buf2_avail - buf2_written E<gt> 0)\n"
"            FD_SET(fd1, &writefds);\n"
"        if (fd2 E<gt> 0 && buf1_avail - buf1_written E<gt> 0)\n"
"            FD_SET(fd2, &writefds);\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (fd1 E<gt> 0) {\n"
"            FD_SET(fd1, &exceptfds);\n"
"            nfds = max(nfds, fd1);\n"
"        }\n"
"        if (fd2 E<gt> 0) {\n"
"            FD_SET(fd2, &exceptfds);\n"
"            nfds = max(nfds, fd2);\n"
"        }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "        ready = select(nfds + 1, &readfds, &writefds, &exceptfds, NULL);\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (ready == -1 && errno == EINTR)\n"
"            continue;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (ready == -1) {\n"
"            perror(\"select()\");\n"
"            exit(EXIT_FAILURE);\n"
"        }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (FD_ISSET(h, &readfds)) {\n"
"            socklen_t addrlen;\n"
"            struct sockaddr_in client_addr;\n"
"            int fd;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"            addrlen = sizeof(client_addr);\n"
"            memset(&client_addr, 0, addrlen);\n"
"            fd = accept(h, (struct sockaddr *) &client_addr, &addrlen);\n"
"            if (fd == -1) {\n"
"                perror(\"accept()\");\n"
"            } else {\n"
"                SHUT_FD1;\n"
"                SHUT_FD2;\n"
"                buf1_avail = buf1_written = 0;\n"
"                buf2_avail = buf2_written = 0;\n"
"                fd1 = fd;\n"
"                fd2 = connect_socket(forward_port, argv[3]);\n"
"                if (fd2 == -1)\n"
"                    SHUT_FD1;\n"
"                else\n"
"                    printf(\"connect from %s\\en\",\n"
"                           inet_ntoa(client_addr.sin_addr));\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"                /* Skip any events on the old, closed file\n"
"                   descriptors. */\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"                continue;\n"
"            }\n"
"        }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "        /* NB: read OOB data before normal reads. */\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (fd1 E<gt> 0 && FD_ISSET(fd1, &exceptfds)) {\n"
"            char c;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"            nbytes = recv(fd1, &c, 1, MSG_OOB);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD1;\n"
"            else\n"
"                send(fd2, &c, 1, MSG_OOB);\n"
"        }\n"
"        if (fd2 E<gt> 0 && FD_ISSET(fd2, &exceptfds)) {\n"
"            char c;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"            nbytes = recv(fd2, &c, 1, MSG_OOB);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD2;\n"
"            else\n"
"                send(fd1, &c, 1, MSG_OOB);\n"
"        }\n"
"        if (fd1 E<gt> 0 && FD_ISSET(fd1, &readfds)) {\n"
"            nbytes = read(fd1, buf1 + buf1_avail,\n"
"                          BUF_SIZE - buf1_avail);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD1;\n"
"            else\n"
"                buf1_avail += nbytes;\n"
"        }\n"
"        if (fd2 E<gt> 0 && FD_ISSET(fd2, &readfds)) {\n"
"            nbytes = read(fd2, buf2 + buf2_avail,\n"
"                          BUF_SIZE - buf2_avail);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD2;\n"
"            else\n"
"                buf2_avail += nbytes;\n"
"        }\n"
"        if (fd1 E<gt> 0 && FD_ISSET(fd1, &writefds) && buf2_avail E<gt> 0) {\n"
"            nbytes = write(fd1, buf2 + buf2_written,\n"
"                           buf2_avail - buf2_written);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD1;\n"
"            else\n"
"                buf2_written += nbytes;\n"
"        }\n"
"        if (fd2 E<gt> 0 && FD_ISSET(fd2, &writefds) && buf1_avail E<gt> 0) {\n"
"            nbytes = write(fd2, buf1 + buf1_written,\n"
"                           buf1_avail - buf1_written);\n"
"            if (nbytes E<lt> 1)\n"
"                SHUT_FD2;\n"
"            else\n"
"                buf1_written += nbytes;\n"
"        }\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid "        /* Check if write data has caught read data. */\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (buf1_written == buf1_avail)\n"
"            buf1_written = buf1_avail = 0;\n"
"        if (buf2_written == buf2_avail)\n"
"            buf2_written = buf2_avail = 0;\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        /* One side has closed the connection, keep\n"
"           writing to the other side until empty. */\n"
msgstr ""

#. type: Plain text
#: debian-bookworm opensuse-leap-15-6
#, no-wrap
msgid ""
"        if (fd1 E<lt> 0 && buf1_avail - buf1_written == 0)\n"
"            SHUT_FD2;\n"
"        if (fd2 E<lt> 0 && buf2_avail - buf2_written == 0)\n"
"            SHUT_FD1;\n"
"    }\n"
"    exit(EXIT_SUCCESS);\n"
"}\n"
msgstr ""

#. type: TH
#: debian-unstable opensuse-tumbleweed
#, no-wrap
msgid "2023-05-03"
msgstr ""

#. type: TH
#: debian-unstable opensuse-tumbleweed
#, no-wrap
msgid "Linux man-pages 6.05.01"
msgstr ""

#. type: TH
#: opensuse-leap-15-6
#, no-wrap
msgid "Linux man-pages 6.04"
msgstr ""