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/exits.3 | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 man/man3/exits.3 (limited to 'man/man3/exits.3') diff --git a/man/man3/exits.3 b/man/man3/exits.3 new file mode 100644 index 00000000..c242cb0e --- /dev/null +++ b/man/man3/exits.3 @@ -0,0 +1,81 @@ +.TH EXITS 3 +.SH NAME +exits, _exits, atexit, atexitdont, terminate \- terminate process, process cleanup +.SH SYNOPSIS +.B #include +.br +.B #include +.PP +.nf +.B +void _exits(char *msg) +.B +void exits(char *msg) +.PP +.B +int atexit(void(*)(void)) +.PP +.B +void atexitdont(void(*)(void)) +.fi +.SH DESCRIPTION +.I Exits +is the conventional way to terminate a process. +.I _Exits +is the underlying system call. +They +can never return. +.PP +.I Msg +conventionally includes a brief (maximum length +.BR ERRLEN ) +explanation of the reason for +exiting, or a null pointer or empty string to indicate normal termination. +The string is passed to the parent process, prefixed by the name and process +id of the exiting process, when the parent does a +.IR wait (2). +.PP +Before calling +.I _exits +with +.I msg +as an argument, +.I exits +calls in reverse order all the functions +recorded by +.IR atexit . +.PP +.I Atexit +records +.I fn +as a function to be called by +.IR exits . +It returns zero if it failed, +nonzero otherwise. +A typical use is to register a cleanup routine for an I/O package. +To simplify programs that fork or share memory, +.I exits +only calls those +.IR atexit -registered +functions that were registered by the same +process as that calling +.IR exits . +.PP +Calling +.I atexit +twice (or more) with the same function argument causes +.I exits +to invoke the function twice (or more). +.PP +There is a limit to the number of exit functions +that will be recorded; +.I atexit +returns 0 if that limit has been reached. +.PP +.I Atexitdont +cancels a previous registration of an exit function. +.SH SOURCE +.B /sys/src/libc/port/atexit.c +.SH "SEE ALSO" +.IR fork (2), +.IR wait (2) -- cgit v1.2.3