MONCONTROL(3)              Library Functions Manual              MONCONTROL(3)

NAME
     moncontrol, monstartup -- control execution profile

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     moncontrol(int mode);

     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().

ENVIRONMENT
     PROFDIR  Directory to place the output file(s) in.  When this is set,
              instead of writing the profiling output to gmon.out, a filename
              is generated from the process id and name of the program (e.g.,
              123.a.out).  If you are profiling a program that forks, or
              otherwise creates multiple copies, setting this is the only
              reasonable way to get all profiling data.

FILES
     gmon.out      execution data file

SEE ALSO
     cc(1), gprof(1), profil(2)

NetBSD 7.99                      June 4, 1993                      NetBSD 7.99