CLOCK(S) UNIX System V CLOCK(S)
Name
clock - report CPU time used
Syntax
long clock ( )
Description
The clock function returns the amount of CPU time (in
microseconds) used since the first call to clock. The time
reported is the sum of the user and system times of the
calling process and its terminated child processes for which
it has executed wait(S), pclose(S), or system(S).
The resolution of the clock is 10 milliseconds.
See Also
times(S), wait(S), popen(S), system(S).
Notes
The value returned by clock is defined in microseconds for
compatibility with systems that have CPU clocks with much
higher resolution. Because of this, the value returned will
wrap around after accumulating only 2147 seconds of CPU time
(about 36 minutes).
Standards Conformance
clock is conformant with:
AT&T SVID Issue 2, Select Code 307-127;
The X/Open Portability Guide II of January 1987;
and ANSI X3.159-198X C Language Draft Standard, May 13,
1988.
(printed 6/20/89)