Name
profil — execution time profile
Synopsis
#include <unistd.h>
int
profil( |
unsigned short * | buf, |
| size_t | bufsiz, | |
| size_t | offset, | |
| unsigned int | scale); |
![[Note]](../stylesheet/note.png) |
Note | ||
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DESCRIPTION
This routine provides a means to find out in what areas
your program spends most of its time. The argument buf points to bufsiz bytes of core. Every
virtual 10 milliseconds, the user's program counter (PC) is
examined: offset is
subtracted and the result is multiplied by scale and divided by 65536. If
the resulting value is less than bufsiz, then the corresponding
entry in buf is
incremented. If buf
is NULL, profiling is disabled.
BUGS
profil() cannot be used on a
program that also uses ITIMER_PROF itimers.
True kernel profiling provides more accurate results. Libc 4.4 contained a kernel patch providing a system call profil.