need help with a basic loop

Hi.
I'm new to unix and am stumped on this problem. . .. I've a file that contains a text list consisting of names some of which are like "currentfile-sm", and for each of these with an "-sm" I'd like to delete. My loop is as follows:

for i in `cat allItems.lis`
do
sed 's/[a-zA-Z1-9][a-zA-Z1-9]*[-sm]/ /g'
done

but it hangs! Can anyone tell me where I'm going wrong? I'm attempting this in both the ksh and sh shell, niether of which will work.

You're not actually applying the sed command to anything.

You'd need
echo $i |sed ....

Not sure what your sed command is trying to achieve but that was why it was hanging.

If I understand you correctly then you have a file listing files you want to remove (those ending with -sm) and other files you want to keep. If this is the case then I'd do the following:

List all the files you want to delete:
grep "-sm$" allItems.lis

Confirm you're happy you're only listing the ones you want to delete, then add the remove command (this assumes there's only one field on each line):
grep "-sm$" allItems.lis |awk '{print "rm "$1}'

Confirm these commands look ok, then run:
grep "-sm$" allItems.lis |awk '{print "rm "$1}' |ksh -x

andy is correct, and your sed
sed 's/[a-zA-Z1-9][a-zA-Z1-9]*[-sm]/ /g'
match:
abba1-
abba1s
abba1m
changing all three to a space
never matching 'abba1-sm'

the unix cmd: rm [A-z1-9]*[A-z1-9]-sm
will do the job