diff options
Diffstat (limited to 'man2/dup.2')
| -rw-r--r-- | man2/dup.2 | 38 |
1 files changed, 23 insertions, 15 deletions
diff --git a/man2/dup.2 b/man2/dup.2 index 85dac61ff..b7187ed59 100644 --- a/man2/dup.2 +++ b/man2/dup.2 @@ -14,7 +14,7 @@ .\" details for dup2(). .\" 2008-10-09, mtk: add description of dup3() .\" -.TH dup 2 2023-02-05 "Linux man-pages 6.03" +.TH dup 2 2023-05-03 "Linux man-pages 6.05.01" .SH NAME dup, dup2, dup3 \- duplicate a file descriptor .SH LIBRARY @@ -197,20 +197,28 @@ The per-process limit on the number of open file descriptors has been reached .B RLIMIT_NOFILE in .BR getrlimit (2)). -.SH VERSIONS -.BR dup3 () -was added in Linux 2.6.27; -glibc support is available since glibc 2.9. .SH STANDARDS -.BR dup (), -.BR dup2 (): -POSIX.1-2001, POSIX.1-2008, SVr4, 4.3BSD. -.PP +.TP +.BR dup () +.TQ +.BR dup2 () +POSIX.1-2008. +.TP .BR dup3 () -is Linux-specific. +Linux. +.SH HISTORY +.TP +.BR dup () +.TQ +.BR dup2 () +POSIX.1-2001, SVr4, 4.3BSD. .\" SVr4 documents additional .\" EINTR and ENOLINK error conditions. POSIX.1 adds EINTR. .\" The EBUSY return is Linux-specific. +.TP +.BR dup3 () +Linux 2.6.27, +glibc 2.9. .SH NOTES The error returned by .BR dup2 () @@ -247,21 +255,21 @@ Instead, code something like the following could be used: /* Obtain a duplicate of \[aq]newfd\[aq] that can subsequently be used to check for close() errors; an EBADF error means that \[aq]newfd\[aq] was not open. */ - +\& tmpfd = dup(newfd); if (tmpfd == \-1 && errno != EBADF) { /* Handle unexpected dup() error. */ } - +\& /* Atomically duplicate \[aq]oldfd\[aq] on \[aq]newfd\[aq]. */ - +\& if (dup2(oldfd, newfd) == \-1) { /* Handle dup2() error. */ } - +\& /* Now check for close() errors on the file originally referred to by \[aq]newfd\[aq]. */ - +\& if (tmpfd != \-1) { if (close(tmpfd) == \-1) { /* Handle errors from close. */ |