Kevin Martin wrote: > So I'm fairly confused at this point. > > Start with a /bin/sh shell. > > Then do: > > sh-3.2$ unset $? > sh: unset: `0': not a valid identifier > > ok, no problem; then do > > sh-3.2$ /bin/ksh -c " set -xv ; grep ABCD b ; echo $? ; if [ "$?" = > "0" ] ; then echo yes ; fi" > + grep ABCD b > ABCD="C" ; export ABCD > + echo 1 > 1 > + [ 1 = 0 ] > > WHAT? > > Then do it again without unsetting $?: > sh-3.2$ /bin/ksh -c " set -xv ; grep ABCD b ; echo $? ; if [ "$?" = "0" > ] ; then echo yes ; fi" > + grep ABCD b > ABCD="C" ; export ABCD > + echo 0 > 0 > + [ 0 = 0 ] > + echo yes > yes > > > Why doesn't the first iteration work? Is this a ksh bug? > > > I don't think you are testing what you think you are testing.... I believe that when you execute "ksh -c" you won't get a return value for the commands in the string as you have them listed. Take the 3 potential return codes for grep. 0 = string found 1 = string not found 2 = file not found $ cat b ABCD $ grep ABCD b ABCD $ echo $? 0 $ grep K b $ echo $? 1 $ grep ABCD kkk grep: kkk: No such file or directory $ echo $? 2 $ ksh -c "set -xv ; grep ABCD kkk ; echo $?" + grep ABCD kkk grep: kkk: No such file or directory + echo 0 0 Clearly the "echo $?" is not returning the code from grep...but from the last command of the parent shell... As in.... $ grep ABCD kkk grep: kkk: No such file or directory $ ksh -c "set -xv ; grep ABCD kkk ; echo $?" + grep ABCD kkk grep: kkk: No such file or directory + echo 2 2 I don't do much shell scripting these days....but it may not even be the result of "ksh -c" it could just be what is true when you use ";" to string commands together on the same line. -- Car sickness is the feeling you get when the monthly car payment is due. -- fedora-list mailing list fedora-list@xxxxxxxxxx To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
