Probably because you've got ret = $? or some other variant with spaces around the =. And the second is just plain wrong, as the $ is for interpolating in shell not a universal variable prefix. At any rate, it's not a perl problem; you need to look into something like Learning the bash Shell (ISBN 1565923472) or the Z shell intro.

#!/usr/bin/sh
echo /usr/bin/perl perlscript.pl
ret=$?
echo "Status String is $?"
if [ $ret -eq 0 ]
then
  echo "case A"
else
  echo "case B"
fi
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Status String is 0
case A
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Thanks a lot!
But how do I force it to exit with the status string?
What I mean is that if the executing of perl pgm fails for some reason, I want it to be forced to exit the script. Else, if it is success, then ftp a file.
exit $ret OR return $? doesn't work

That could be done like that:

#!/usr/bin/sh
echo /usr/bin/perl perlscript.pl
ret=$?
echo "Status String is $?"
if [ $ret -eq 0 ]
then
  echo "case A"
else
  echo "case B"
fi
echo going to exit shell with $ret
exit $ret
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In this example we treat the return code of "echo" which is always 0 of course. But ist will also work when you remove the echoing and execute the perlscript instead.
pelagic

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I can resist anything but temptation.