Count for how many files can a Unix command be executed - linux

Question

So I'm given a directory in $dir and an Unix command in $1 I need to check how many files are in $dir directory to which the $1 Unix command can be executed.
for dir in `echo $PATH|tr : '\n'`
do
for file in `find $dir -type f`
do
#Here I would like to check if the command works on the file
then
echo " $1 $dir/$file works"
else
echo " $1 $dir/$file doesn't work"
fi
done
done

Answer 1

It appears that you want to search through all the files in the PATH and, for each file, see if command $1 succeeds or fails with that file as an argument. In that case:
#!/bin/bash
(IFS=:
find $PATH -type f -exec bash -c 'if "$1" "$2"; then echo "$1 $2 works"; else echo "$1 $2 fails"; fi' None "$1" {} \;
)
Or, for greater efficiency:
(IFS=:
find $PATH -type f -exec bash -c 'cmd=$1; shift; for f in "$#"; do if "$cmd" "$f"; then echo "$cmd $f works"; else echo "$cmd $f fails"; fi; done' None "$1" {} +
)
How it works
(
This starts a subshell. This is done so that IFS returns to its original value after the subshell finishes.
IFS=:
This tells the shell to do word splitting on :.
find $PATH -type f -exec bash -c '...' None "$1" {} +
This looks for all regular files underneath directories that are in the PATH and executes the commands in '...' on them.
More specifically, the commands in '...' are given as positional arguments, the name of the command $1 and one or more (probably many) files to test as arguments.
The commands in '...' are:
cmd=$1
shift
for f in "$#"; do
if "$cmd" "$f"
then echo "$cmd $f works"
else echo "$cmd $f fails"
fi
done
These commands test if the command succeeded and report the results.
)
This closes the subshell
Silencing the output from the commands
As glenn jackman suggests, you might not want to see the output from each run of the command $1 and instead just keep track of whether it succeeded or failed. In that case, we can redirect the command's output to /dev/null as follows:
#!/bin/bash
(IFS=:; find $PATH -type f -exec bash -c 'if "$1" "$2" >/dev/null 2>&1; then echo "$1 $2 works"; else echo "$1 $2 fails"; fi' None "$1" {} \; )
When this is done, the output may look like:
$ bash scriptname ls
ls /bin/keyctl works
ls /bin/mt-gnu works
ls /bin/uncompress works
ls /bin/nano works
ls /bin/zless works
ls /bin/run-parts works
[...snip...]