NAME
moncontrol,
monstartup —
control execution profile
SYNOPSIS
#include
<sys/gmon.h>
void
moncontrol(int
mode);
void
monstartup(u_long
lowpc, u_long
highpc);
DESCRIPTION
An executable program compiled using the
-pg option to
cc(1)
automatically includes calls to collect statistics for the
gprof(1)
call-graph execution profiler. In typical operation, profiling begins at
program startup and ends when the program calls exit. When the program
exits, the profiling data are written to the file
gmon.out,
then gprof(1) can be used to examine the results.
moncontrol()
selectively controls profiling within a program. When the program starts,
profiling begins. To stop the collection of histogram ticks and call counts
use moncontrol(0); to resume
the collection of histogram ticks and call counts use
moncontrol(1). This feature
allows the cost of particular operations to be measured. Note that an output
file will be produced on program exit regardless of the state of
moncontrol().
Programs that are not loaded with
-pg may selectively collect profiling statistics by
calling
monstartup()
with the range of addresses to be profiled. lowpc and
highpc specify the address range that is to be
sampled; the lowest address sampled is that of lowpc
and the highest is just below highpc. Only functions
in that range that have been compiled with the -pg
option to cc(1)
will appear in the call graph part of the output; however, all functions in
that address range will have their execution time measured. Profiling begins
on return from monstartup().
FILES
- gmon.out
- execution data file