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Diffstat (limited to 'examples/functions/substr')
-rw-r--r-- | examples/functions/substr | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/examples/functions/substr b/examples/functions/substr new file mode 100644 index 0000000..f19f5d7 --- /dev/null +++ b/examples/functions/substr @@ -0,0 +1,97 @@ +# +# Chet Ramey <chet.ramey@case.edu> +# +# Copyright 2002 Chester Ramey +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2, or (at your option) +# any later version. +# +# TThis program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software Foundation, +# Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. +# +# substr -- a function to emulate the ancient ksh builtin +# + +# +# -l == shortest from left +# -L == longest from left +# -r == shortest from right (the default) +# -R == longest from right + +substr() +{ + local flag pat str + local usage="usage: substr -lLrR pat string or substr string pat" + + case "$1" in + -l | -L | -r | -R) + flag="$1" + pat="$2" + shift 2 + ;; + -*) + echo "substr: unknown option: $1" + echo "$usage" + return 1 + ;; + *) + flag="-r" + pat="$2" + ;; + esac + + if [ "$#" -eq 0 ] || [ "$#" -gt 2 ] ; then + echo "substr: bad argument count" + return 2 + fi + + str="$1" + + # + # We don't want -f, but we don't want to turn it back on if + # we didn't have it already + # + case "$-" in + "*f*") + ;; + *) + fng=1 + set -f + ;; + esac + + case "$flag" in + -l) + str="${str#$pat}" # substr -l pat string + ;; + -L) + str="${str##$pat}" # substr -L pat string + ;; + -r) + str="${str%$pat}" # substr -r pat string + ;; + -R) + str="${str%%$pat}" # substr -R pat string + ;; + *) + str="${str%$2}" # substr string pat + ;; + esac + + echo "$str" + + # + # If we had file name generation when we started, re-enable it + # + if [ "$fng" = "1" ] ; then + set +f + fi +} |