RE: Static vs. Dynamic storage (was Activation groups for beginners)

Just a little further explanation about static variables in procedures.

In a procedure declared with static storage for variables, there is not real
"sharing", the procedure is simply reusing the same variable without
reinitializing it.

Given our incrAndDisplay procedure in AG AG2 called from MyProg in AG1:

Entry: MyProg (AG1)
Inside MyProg: calls MyProc (AG2)
     CountStatic and CountAuto initialized to 0.  CountStaticInz and
CountAutoInz incremented to 10.
  MyProc returns
Inside MyProg: calls MyProc (AG2)
     Countauto initialized to 0.  CountAutoInz initialized to 10.
     Static variables CountStatic and CountStaticInz retain last value.

Static simply means, don't reinitialize them.

Static variables are not shared, but simply reused.

If, at any time, AG2 is reclaimed, when the procedure is called again the
initialization phase for the static variables would take place.

Regards,

Jim Langston

h debug dftactgrp(*no) actgrp('QILE') option(*srcstmt: *nodebugio)
 * dbgview(*list)

d incrAndDisplay  pr

c                   callp     incrAndDisplay
c                   eval      *inlr = *on

p incrAndDisplay  b
d incrAndDisplay  pi

d countStatic     s             10i 0 static
d countStaticInz  s             10i 0 static inz(10)
d countAuto       s             10i 0
d countAutoInz    s             10i 0 inz(10)

c                   eval      countStatic    = countStatic    + 1
c                   eval      countStaticInz = countStaticInz + 1
c                   eval      countAuto      = countAuto      + 1
c                   eval      countAutoInz   = countAutoInz   + 1
c     countStatic   dsply
c     countStaticInzdsply
c     countAuto     dsply
c     countAutoInz  dsply

p                 e