Remove errors at command line

[Vanquish]

i am doing a diff between 2 files if the file does not exists it gives error message on command line i want to remove it
diff: No such file or directory
Thanks

[Marvin Strong · Accepted solution]

add 2>/dev/null to the end of your diff command.

example

diff file1 file2 2>/dev/null

[Juergen Tappe]

Easy answer :
diff file1 file2 2>/dev/null

and the error messages going to "trashcan".

Juergen

[A. Clay Stephenson]

That error message goers to stderr (like good UNIX programs should) while the normal output goes to stdout. The solution is simple:

diff file1 file2 2>/dev/null

[Hazem Mahmoud_3]

# diff file1 file2 2 > /dev/null

-Hazem

[A. Clay Stephenson]

I should add that there is a danger to ignoring the error message. It now is not possible to distinguish between two files which match exactly (ie no diff) and a missing file. Both cases will result in no output to stdout. You need to now check the status of the diff command as well as examine stdout. Diff will return a non-zero exit status on failure.

e.g.
diff file1 file2 2>/dev/null > difffile
STAT=${?}
if [[ ${STAT} -ne 0 ]]
then
echo "Diff failed. Status = ${STAT}"
fi

[Rory R Hammond]

From a Shell Script:

if
[ -f file1 -a -f file2 ]
then
diff file1 file2
fi

Suggest if you want from a command line:
1. make a function in .profile

difff()
{
if
[ -f $1 -a -f $2 ]
then
diff $1 $2
fi
}

2. command line
difff file1 file2