clock -- determine processor time used
Standard C Library (libc, -lc)
The clock() function determines the amount of processor time used since
the invocation of the calling process, measured in CLOCKS_PER_SECs of a
The clock() function returns the amount of time used unless an error
occurs, in which case the return value is -1.
The clock() function conforms to ISO/IEC 9899:1990 (``ISO C89''). However,
Version 2 of the Single UNIX Specification (``SUSv2'') requires
CLOCKS_PER_SEC to be defined as one million. FreeBSD does not conform to
this requirement; changing the value would introduce binary incompatibility
and one million is still inadequate on modern processors.
FreeBSD 5.2.1 June 4, 1993 FreeBSD 5.2.1 [ Back ]