Diff command in bash -

every time run following bash command, error:

here's code:

sort -b ./tests/out/$scenario > $studentfile sort -b ./tests/out/$scenario > $proffile $(diff $studentfile $proffile)   if [ $? -eq 0 ]                  echo "files equal!"       else           echo "files different!"       fi 

here's error:

./test.sh: 2c2: not found 

i want sort 2 files, , check if equal or not. don't understand error means , how can rid of it. appreciated.

thanks!

short answer: use

diff $studentfile $proffile 

instead of:

$(diff $studentfile $proffile) 

long answer:

diff $studentfile $proffile  

wil provide output of several lines, first one, in example, "2c2". if enclose diff command in $(), result of expression "2c2 ...". result taken bash new command, result of "command not found: 2c2".

compare, example:

$(diff $studentfile $proffile) 

and:

echo $(diff $studentfile $proffile) 

* addendum *

if diff $studentfile $proffile > /dev/null 2>&1   echo "equal files" else   echo "different files" fi