I have the following bash script:

STDIN='&0'
if some-condition; then
  STDIN=some-filename
fi

run-command <${STDIN}

But that errors with &0: No such file or directory.

Similarly for STDOUT.

I’ve tried using eval but haven’t gotten that to work, either.

What needs to be done to get this to work?

>Solution :

STDIN=’/dev/stdin’ # Default to stdin

if some-condition; then

STDIN=’some-filename’

fi

Similarly, for STDOUT

STDOUT=’/dev/stdout’ # Default to stdout

if some-other-condition; then

STDOUT=’some-other-filename’

fi

run-command <"$STDIN" >"$STDOUT"