Cmail - C or perl or whatever

[Paul O'Neill]

In article <14810 at bfmny0.UU.NET> tneff at bfmny0.UU.NET (Tom Neff) writes:
>
>And please note that the cute device
>
>	#!/usr/bin/perl [-flags]
>
>which lets some users run perl scripts directly by name as ziplessly as
>if they were standalone executables, DOES NOT WORK everywhere.  On my
>system, it would be necessary to create companion shell scripts or Korn
>shell aliases to invoke any such script.
>

Perl is so cool.  From the man page:

     -S   makes perl use the PATH environment variable to  search
          for  the  script  (unless the name of the script starts
          with a slash).  Typically this is used  to  emulate  #!
          startup  on machines that don't support #!, in the fol-
          lowing manner:

               #!/usr/bin/perl
               eval "exec /usr/bin/perl -S $0 $*"
                    if $running_under_some_shell;

          The system ignores the first line and feeds the  script
          to  /bin/sh,  which proceeds to try to execute the perl
          script as a  shell  script.   The  shell  executes  the
          second  line as a normal shell command, and thus starts
          up the perl interpreter.  On some  systems  $0  doesn't
          always  contain the full pathname, so the -S tells perl
          to search for the  script  if  necessary.   After  perl
          locates  the  script,  it  parses the lines and ignores
          them because the variable $running_under_some_shell  is
          never true.

Tom Christiansen obviously wrote the program to show off the language, not
to do the job.  Take a hint.  You're not out in the cold if your vendor
didn't supply it.  Scarf it, install it.  You and your users will thank you.


Paul O'Neill                 pvo at oce.orst.edu
Coastal Imaging Lab
OSU--Oceanography
Corvallis, OR  97331         503-754-3251