PATHETICALLY simple diff script question.

[Steve Post]

I haven't had my coffee yet. I am ashamed to ask. But.....

I have two files: A and B.

I would like a snippet of shell code.

if [ ??????? ] ; then
echo " the files are the same"
else
echo " the files are different"
fi

I don't need to know the exact differences, just that they ARE different.

steve

[Slawomir Gora · Accepted solution]

Hi,

install md5sum package and check

if [ "`md5sum A | awk '{print $1}'`" = "`md5sum B | awk '{print $1}'`" ]
then
echo "the files are the same"
else
echo " the files are different"
fi

[Slawomir Gora]

Hi,

or using diff

A=file1
B=file2

if [ "`diff $A $B`" = "" ]
then
echo "the files are the same"
else
echo " the files are different"
fi

[Steve Post]

Thanks. I see I gave you 20 points. But they are two distinct answers.

Steve

[Dave Olker]

Hi Steve,

The simplest case would be something like:

diff file1 file2 > /dev/null 2>&1

if [ $? -eq 0 ]
then
echo "the files are the same"
else
echo "the files are different"
fi


Of course, you'd probably want to first make sure "file1" and "file2" exist, and you'd also want the ksh program to take the file names as arguments. You could also call cksum against the two files and compare the output, but the above syntax should work for using diff against two files.

Regards,

Dave

[Simon Hargrave]

diff returns 0 if no differences, 1 if differences or >1 if error. So: -

diff file1 file2 2>&1 >/dev/null
if [ $? -eq 0 ]; then
echo "The files are the same"
elif [ $? -eq 1 ]; then
echo "The files are different"
else
echo "There was an error"
fi

[Steve Post]

ok. closing thread now.

Got lots of good answers. THANKS.