TCSH: 'Can't find string terminator' Error From perl -e in TCSH Script

Question

I'm seeing this error from my tcsh script and I can't figure out why.

Script:

#!/usr/bin/env tcsh
foreach n (0 1)
  set PERL_CMD = "perl -e 'print qq^RUNNING^; exit ${n} '"
  echo "PERL_CMD:\n${PERL_CMD}"
  ${PERL_CMD}
  echo
end

Result:

[]$ ./test_perl_e.csh
PERL_CMD:
perl -e 'print qq^RUNNING^; exit 0 '
Can't find string terminator "'" anywhere before EOF at -e line 1.
PERL_CMD:
perl -e 'print qq^RUNNING^; exit 1 '
Can't find string terminator "'" anywhere before EOF at -e line 1.

Running either of those PERL_CMD on the command line works fine:

[]$ perl -e 'print qq^RUNNING^; exit 1 '
RUNNING[]$ 

When I embed into a tcsh script, it echo's back fine. However when I try to run it, it's broken.

I've tried a bunch of variations, but I'm stumped. What did I do wrong?

---

Using perl/5.24

[]$ perl -v
This is perl 5, version 24, subversion 0 (v5.24.0) built for x86_64-linux

Answer 1

The idiomatic way to do in cshell, what you are trying to do , is to a) use arrays and b) employ proper quoting operators. You can read up on them in man tcsh.

#!/usr/bin/env tcsh
set perl = "perl"
set options = ( -w -l )
foreach n (0 9)
  set cmd = "

    print qq/running/;

    exit($n); 

  "
"${perl}" 

    ${options[*]:x} 

    -e ${cmd:q}  

  ;
echo ""
end