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Diffstat (limited to 'man2/times.2')
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diff --git a/man2/times.2 b/man2/times.2 deleted file mode 100644 index 0c14bd6e9..000000000 --- a/man2/times.2 +++ /dev/null @@ -1,222 +0,0 @@ -.\" Copyright (c) 1992 Drew Eckhardt (drew@cs.colorado.edu), March 28, 1992 -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Modified by Michael Haardt (michael@moria.de) -.\" Modified Sat Jul 24 14:29:17 1993 by Rik Faith (faith@cs.unc.edu) -.\" Modified 961203 and 001211 and 010326 by aeb@cwi.nl -.\" Modified 001213 by Michael Haardt (michael@moria.de) -.\" Modified 13 Jun 02, Michael Kerrisk <mtk.manpages@gmail.com> -.\" Added note on nonstandard behavior when SIGCHLD is ignored. -.\" Modified 2004-11-16, mtk, Noted that the nonconformance when -.\" SIGCHLD is being ignored is fixed in Linux 2.6.9; other minor changes -.\" Modified 2004-12-08, mtk, in Linux 2.6 times() return value changed -.\" 2005-04-13, mtk -.\" Added notes on nonstandard behavior: Linux allows 'buf' to -.\" be NULL, but POSIX.1 doesn't specify this and it's nonportable. -.\" -.TH times 2 (date) "Linux man-pages (unreleased)" -.SH NAME -times \- get process times -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <sys/times.h> -.PP -.BI "clock_t times(struct tms *" buf ); -.fi -.SH DESCRIPTION -.BR times () -stores the current process times in the -.I "struct tms" -that -.I buf -points to. -The -.I struct tms -is as defined in -.IR <sys/times.h> : -.PP -.in +4n -.EX -struct tms { - clock_t tms_utime; /* user time */ - clock_t tms_stime; /* system time */ - clock_t tms_cutime; /* user time of children */ - clock_t tms_cstime; /* system time of children */ -}; -.EE -.in -.PP -The -.I tms_utime -field contains the CPU time spent executing instructions -of the calling process. -The -.I tms_stime -field contains the CPU time spent executing inside the kernel -while performing tasks on behalf of the calling process. -.PP -The -.I tms_cutime -field contains the sum of the -.I tms_utime -and -.I tms_cutime -values for all waited-for terminated children. -The -.I tms_cstime -field contains the sum of the -.I tms_stime -and -.I tms_cstime -values for all waited-for terminated children. -.PP -Times for terminated children (and their descendants) -are added in at the moment -.BR wait (2) -or -.BR waitpid (2) -returns their process ID. -In particular, -times of grandchildren -that the children did not wait for are never seen. -.PP -All times reported are in clock ticks. -.SH RETURN VALUE -.BR times () -returns the number of clock ticks that have elapsed since -an arbitrary point in the past. -The return value may overflow the possible range of type -.IR clock_t . -On error, -\fI(clock_t)\ \-1\fP is returned, -and -.I errno -is set to indicate the error. -.SH ERRORS -.TP -.B EFAULT -.I tms -points outside the process's address space. -.SH VERSIONS -On Linux, -the -.I buf -argument can be specified as NULL, -with the result that -.BR times () -just returns a function result. -However, -POSIX does not specify this behavior, -and most -other UNIX implementations require a non-NULL value for -.IR buf . -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001, -SVr4, -4.3BSD. -.PP -In POSIX.1-1996 the symbol \fBCLK_TCK\fP (defined in -.IR <time.h> ) -is mentioned as obsolescent. -It is obsolete now. -.PP -Before Linux 2.6.9, -if the disposition of -.B SIGCHLD -is set to -.BR SIG_IGN , -then the times of terminated children -are automatically included in the -.I tms_cstime -and -.I tms_cutime -fields, -although POSIX.1-2001 says that this should happen -only if the calling process -.BR wait (2)s -on its children. -This nonconformance is rectified in Linux 2.6.9 and later. -.\" See the description of times() in XSH, which says: -.\" The times of a terminated child process are included... when wait() -.\" or waitpid() returns the process ID of this terminated child. -.PP -On Linux, -the \[lq]arbitrary point in the past\[rq] -from which the return value of -.BR times () -is measured has varied across kernel versions. -On Linux 2.4 and earlier, -this point is the moment the system was booted. -Since Linux 2.6, -this point is \fI(2\[ha]32/HZ) \- 300\fP -seconds before system boot time. -This variability across kernel versions (and across UNIX implementations), -combined with the fact that the returned value may overflow the range of -.IR clock_t , -means that a portable application would be wise to avoid using this value. -To measure changes in elapsed time, -use -.BR clock_gettime (2) -instead. -.\" .PP -.\" On older systems the number of clock ticks per second is given -.\" by the variable HZ. -.PP -SVr1-3 returns -.I long -and the struct members are of type -.I time_t -although they store clock ticks, -not seconds since the Epoch. -V7 used -.I long -for the struct members, -because it had no type -.I time_t -yet. -.SH NOTES -The number of clock ticks per second can be obtained using: -.PP -.in +4n -.EX -sysconf(_SC_CLK_TCK); -.EE -.in -.PP -Note that -.BR clock (3) -also returns a value of type -.IR clock_t , -but this value is measured in units of -.BR CLOCKS_PER_SEC , -not the clock ticks used by -.BR times (). -.SH BUGS -A limitation of the Linux system call conventions on some architectures -(notably i386) means that on Linux 2.6 there is a small time window -(41 seconds) soon after boot when -.BR times () -can return \-1, -falsely indicating that an error occurred. -The same problem can occur when the return value wraps past -the maximum value that can be stored in -.BR clock_t . -.\" The problem is that a syscall return of -4095 to -1 -.\" is interpreted by glibc as an error, and the wrapper converts -.\" the return value to -1. -.\" http://marc.info/?l=linux-kernel&m=119447727031225&w=2 -.\" "compat_sys_times() bogus until jiffies >= 0" -.\" November 2007 -.SH SEE ALSO -.BR time (1), -.BR getrusage (2), -.BR wait (2), -.BR clock (3), -.BR sysconf (3), -.BR time (7) |