Editing ShellQuoting

Quoting can be such a headache for the novice, in shell programming, and especially in awk. Art Povelones posted a long tutorial on shell quoting on 1999/09/30 which is probably too much detail to repeat with the FAQ; if you could use it, search via <http://groups.google.com/>. Tim Maher offered his <http://www.consultix-inc.com/quoting.txt>. This approach is probably the best, and easiest to understand and maintain, for most purposes: (the '@@' is quoted to ensure the shell will copy verbatim, not interpreting environment variable substitutions etc.) {{{ cat <<'@@' > /tmp/never$$.awk { print "Never say can't." } @@ awk -f /tmp/never$$.awk; rm /tmp/never$$.awk }}} If you enjoy testing your shell's quoting behavior frequently, you could try these: {{{ (see below for a verbose explanation of the first one, with 7 quotes) awk 'BEGIN { q="'"'"'";print "Never say can"q"t."; exit }' nawk -v q="'" 'BEGIN { print "Never say can"q"t."; exit }' awk 'BEGIN { q=sprintf("%c",39); print "Never say can"q"t."; exit }' awk 'BEGIN { q=sprintf("%c",39); print "Never say \"can"q"t.\""; exit }' }}} However, you would also have to know why you could not use this: {{{ awk 'BEGIN { q="\'"; print "Never say \"can"q"t.\""; exit }' }}} explanation of the 7-quote example: note that it is quoted three different ways: {{{ awk 'BEGIN { q="' "'" '";print "Never say can"q"t."; exit }' }}} and that argument comes out as the single string (with embedded spaces) {{{ BEGIN { q="'";print "Never say can"q"t."; exit } }}} which is the same as {{{ BEGIN { q="'"; print "Never say can" q "t."; exit } ^^^^^^^^^^^^^ ^ ^^ | | | || | | | || vvvvvvvvvvvvv | || Never say can v || ' vv t. }}} which, quite possibly with too much effort to be worth it, gets you {{{ Never say can't. }}}

Summary:

This change is a minor edit.

Username: