esa — Apollo

1.1;esa (external_symbol_address), revision 1.1, 86/07/10
ESA (EXTERNAL_SYMBOL_ADDRESS) -- Display address of external symbol.
usage:  ESA symbol_name


FORMAT

  ESA symbol_name


  ESA  displays the address of an external symbol in an installed library.  This
  command is primarily intended for system-level debugging.

  In addition to displaying the address of an external symbol, ESA returns  TRUE
  to the Shell if the symbol exists in an installed library and FALSE if it does
  not.  This means that you may  use  ESA  in  conjunction  with  the  Shell  IF
  statement  to  determine  whether  or not a library is installed, provided you
  know the name of one of its  symbols.    For  example,  you  might  place  the
  following lines in a Shell script:

       if not esa my_favorite_symbol >/dev/null >?/dev/null then
          inlib my_library
       endif

  Note  that  in  this instance, only the value returned by ESA is relevant; the
  actual address of the symbol does not matter.  Hence  all  textual  output  is
  redirected into /dev/null.


ARGUMENTS

  symbol_name
  (required)          Specify  symbol whose address you wish to display.  ESA is
                     case sensitive with respect to the symbol name.   Lowercase
                     must  be  used  to  refer to symbols defined in FORTRAN and
                     Pascal programs.  Mixed case may be used,  as  needed,  for
                     symbols defined in C programs.


EXAMPLES

    $ esa gpr_$init
    A1580C
    $

  This  command  displays  the address of GPR_$INIT.  This symbol resides within
  the GPR library, which was installed at system startup time.
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