Question

I have written this little script to find executables that are passed as arguments e.g.

./testexec du ls md 

How do I get the script to not output commands that are not found – e.g. not to display error output for “md” command ??

  #!/bin/sh

    for filename in "$@"
    do
    which $filename
    done

Answer 1

If you are using bash, you should use the builtin “type” rather than the external utility “which”. The type command will return a non-zero exit status if the command is not found, which makes it easy to use with a conditional.

for filename in "$@"; do
   if type -P "$filename" >/dev/null; then
       echo "found in PATH: $filename"
   fi
done