MONCONTROL(3) BSD Library Functions Manual MONCONTROL(3)
NAME
moncontrol, monstartup -- control execution profile
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/types.h>
#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 progname.gmon, where progname is the name of the program, then gprof(1) can be used to examine the
results.
The moncontrol() function selectively controls profiling within a program. When the program starts, profiling begins. To stop the collec-
tion 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. The lowpc and highpc arguments 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().
ENVIRONMENT
The following environment variables affect the execution of moncontrol:
PROFIL_USE_PID If set, the pid of the process is inserted into the filename.
FILES
progname.gmon execution data file
SEE ALSO
cc(1), gprof(1), profil(2), clocks(7)
BSD
June 14, 2004 BSD
