MONCONTROL(3)

NAME

     moncontrol, monstartup -- control execution profile

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <sys/types.h>
     #include <sys/gmon.h>

     int
     moncontrol(int mode);

     int
     monstartup(u_long *lowpc, u_long *highpc);

DESCRIPTION

     An executable program compiled using the -pg option to cc(1) automati-
     cally 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 pro-
     gram.  When the program starts, profiling begins.	To stop the collection
     of histogram ticks and call counts use moncontrol(0); to resume the col-
     lection of histogram ticks and call counts use moncontrol(1).  This fea-
     ture 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 pro-
     filed.  The lowpc and highpc arguments specify the address range that is
     to be sampled; the lowest address sampled is that of lowpc and the high-
     est 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

     progname.gmon  execution data file

SEE ALSO

     cc(1), gprof(1), profil(2), clocks(7)