MONITOR(3)                                             MONITOR(3)

          monitor - prepare execution profile

          monitor(lowpc, highpc, buffer, bufsize, nfunc)
          int (*lowpc)(), (*highpc)();
          short buffer[];

          An executable program created by `cc -p' automatically
          includes calls for monitor with default parameters; monitor
          needn't be called explicitly except to gain fine control
          over profiling.

          Monitor is an interface to profil(2). Lowpc and highpc are
          the addresses of two functions; buffer is the address of a
          (user supplied) array of bufsize short integers.  Monitor
          arranges to record a histogram of periodically sampled val-
          ues of the program counter, and of counts of calls of cer-
          tain functions, in the buffer.  The lowest address sampled
          is that of lowpc and the highest is just below highpc. At
          most nfunc call counts can be kept; only calls of functions
          compiled with the profiling option -p of cc(1) are recorded.
          For the results to be significant, especially where there
          are small, heavily used routines, it is suggested that the
          buffer be no more than a few times smaller than the range of
          locations sampled.

          To profile the entire program, it is sufficient to use

               extern etext();
               . . .
               monitor((int) 2, etext, buf, bufsize, nfunc);

          Etext lies just above all the program text, see end(3).

          To stop execution monitoring and write the results on the
          file mon.out, use


          then prof(1) can be used to examine the results.


          prof(1), profil(2), cc(1)