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NAME
     profil - execution time profile

SYNOPSIS
     (profil = 44.; not in assembler)
     sys     profil; buff; bufsiz; offset; scale

     profil(buff, bufsiz, offset, scale)
     char buff[ ];
     int bufsiz, offset, scale;

DESCRIPTION
     Buff points to an area of core whose length (in bytes) is
     given by bufsiz.  After this call, the user's program
     counter (pc) is examined each clock tick (60th second); off-
     set is subtracted from it, and the result multiplied by
     scale.  If the resulting number corresponds to a word inside
     buff, that word is incremented.

     The scale is interpreted as an unsigned, fixed-point frac-
     tion with binary point at the left: 177777(8) gives a 1-1
     mapping of pc's to words in buff; 77777(8)        maps each pair of
     instruction words together.  2(8) maps all    instructions onto
     the beginning of buff (producing a non-interrupting core
     clock).

     Profiling is turned off by giving a scale of 0 or 1.  It is
     rendered ineffective by giving a bufsiz of 0.  Profiling is
     also turned off when an exec is executed but remains on in
     child and parent both after a fork.

SEE ALSO
     monitor (III), prof (I)

DIAGNOSTICS
     -

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