FYI, if I attempt to read into the built-in array variable, GROUPS, this doesn't work:
$ bash -c 'while read GROUPS; do echo $GROUPS; done < /etc/passwd'|wc -l 0 Comparing with dash, I see what the author expected, i.e., that the while loop iterates once per line in /etc/passwd: $ dash -c 'while read GROUPS; do echo $GROUPS; done < /etc/passwd'|wc -l 57 With bash, I can work around that by first doing "unset GROUPS". Is there a moral here, other than to avoid using special variable names? Probably to prefer lower-case variable names.
