How can i pass '<' and '>' to a bash script?

Question

I have bash script to run process in another thread and kill it, if it's hung up after timeout. All works perfectly, BUT when process require '<' as input or '>' to output to another file, it doesn't count them. Code:

#!/bin/bash
($1)&
PID=$!
echo "Program '"$1"' started, PID="$PID
i=1
while [ $i -le 600 ]
    do
    ps -p $PID >> /dev/null
    if [ $? -ne 0 ]
      then
      wait $PID
      exit $? #success, return rc of program
    fi
    i=$(($i+1))
    echo "waiting 1 second..."
    sleep 1
done

#program does not want to exit itself, kill it
echo "killing program..."
kill $PID
exit 1 #failed

i use it like this:

safestart.sh './bzip2 -d  sample2.bz2 -k'

and all is as expected, but if i use somethig like this:

safestart.sh './cc_dry2 < dhryinput > results'

it doesn't get '<' or '>' symbols. I tried already with "". same result, I'm completely at lost here.

Answer 1

solution

The problem is the line:

($1)&

You should use instead:

eval $1 &

See also the following example for better understanding the problem.

example

cmd="echo TEST"
$(${cmd})

gives:

TEST: command not found

cmd="echo TEST"
eval ${cmd}

gives:

TEST