dbatest@samgdeab06:/ora1/oracle>ls test*
test      test.out  test.sql  test.tar

# Here sort takes in the o/p of the preceeding command and acts on it to give us the sorted o/p. This happens becos of the pipe

dbatest@samgdeab06:/ora1/oracle>ls test*&#124sort
test
test.out
test.sql
test.tar

# In the following example, ls cannot take in the i/p from it's standard in. So it just lists out the whole directory, irrespective of the standard i/p.

dbatest@samgdeab06:/ora1/oracle>ls test*&#124ls
1                          doc                        oui                        test.out
NOT                        dsmerror.log               product                    test.sql
afiedt.buf                 email                      spcpkg.lis                 test.tar
app                        findExec                   spctab.lis                 tmp
daily_checklist_space.log  jre                        spcusr.lis
dbadmin                    ls.out                     sppurge.lis
dead.letter                oraInventory               test

# This is where xargs serves us. As you see below,xargs takes the standard i/p, constructs an arguement list and passes that as 'arguements' to the 'ls' command. And 'ls' works on those arguments and gives us the result.

dbatest@samgdeab06:/ora1/oracle>ls test*&#124xargs ls
test      test.out  test.sql  test.tar

 
# As seen below, when used with -i option, xargs replaces {} with the i/p arguements. the test* files are moved to the directory TEST

dbatest@samgdeab06:/ora1/oracle>ls test*&#124xargs -i mv {} TEST
dbatest@samgdeab06:/ora1/oracle>ls TEST
test      test.out  test.sql  test.tar