From cfa37a7b1131abbab2e7d339b451f5f0e3198cc8 Mon Sep 17 00:00:00 2001 From: rsc Date: Sat, 10 Apr 2004 18:53:55 +0000 Subject: Lots of man pages. --- man/man3/dup.3 | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) create mode 100644 man/man3/dup.3 (limited to 'man/man3/dup.3') diff --git a/man/man3/dup.3 b/man/man3/dup.3 new file mode 100644 index 00000000..83f98fe1 --- /dev/null +++ b/man/man3/dup.3 @@ -0,0 +1,42 @@ +.TH DUP 3 +.SH NAME +dup \- duplicate an open file descriptor +.SH SYNOPSIS +.B #include +.br +.B #include +.PP +.B +int dup(int oldfd, int newfd) +.SH DESCRIPTION +Given a file descriptor, +.IR oldfd , +referring to an open file, +.I dup +returns a new file descriptor referring to the same file. +.PP +If +.I newfd +is \-1 the system chooses the lowest available file descriptor. +Otherwise, +.I dup +will use +.I newfd +for the new file descriptor +(closing any old file associated with +.IR newfd ). +File descriptors are allocated dynamically, +so to prevent unwarranted growth of the file descriptor table, +.I dup +requires that +.I newfd +be no greater than 20 more than the highest file descriptor ever used by +the program. +.SH SOURCE +.B /sys/src/libc/9syscall +.SH SEE ALSO +.IR intro (2), +.IR dup (3) +.SH DIAGNOSTICS +Sets +.IR errstr . -- cgit v1.2.3