Shell Programming and Scripting

comm -23 file1 file2

CSCeb69473
CSCsg70355
CSCsl48743

comm file1 file2

man comm

which comm

#!/usr/bin/env bash

# @(#) s1       Demonstrate results from comm.

#  ____
# /
# |   Infrastructure BEGIN

echo
set -o nounset

debug=":"
debug="echo"

## The shebang using "env" line is designed for portability. For
#  higher security, use:
#
#  #!/bin/sh -

## Use local command version for the commands in this demonstration.

set +o nounset
echo "(Versions displayed with local utility \"version\")"
version >/dev/null 2>&1 && version =o $(_eat $0 $1) comm
set -o nounset

echo

FILE1=data1
echo " Input file $FILE1:"
cat $FILE1

echo
FILE2=data2
echo " Input file $FILE2:"
cat $FILE2

# |   Infrastructure END
# \
#  ---

echo
echo " Results from processing:"
comm -23 $FILE1 $FILE2

exit 0

$ ./s1

(Versions displayed with local utility "version")
SunOS 5.10
GNU bash 3.00.16
comm - no version provided for /usr/bin/comm.

 Input file data1:
CSCeb69473
CSCsg70355
CSCsj78917
CSCsj85065
CSCsl48743
CSCsl72823
CSCsl77748

 Input file data2:
CSCsg39295
CSCsj78917
CSCsj85065
CSCsl72823
CSCsl77748

 Results from processing:
CSCeb69473
CSCsg70355
CSCsl48743

LC_ALL=C sort
LC_ALL=C comm
LC_ALL=C join
etc