Imported from ../bash-2.0.tar.gz.

examples/scripts.noah/mktmp.bash

@@ -0,0 +1,66 @@
+# mktmp.bash
+# Author: Noah Friedman <friedman@prep.ai.mit.edu>
+# Created: 1993-02-03
+# Last modified: 1993-02-03
+# Public domain
+
+# Conversion to bash v2 syntax done by Chet Ramey
+
+# Commentary:
+# Code:
+
+#:docstring mktmp:
+# Usage: mktmp [template] {createp}
+#
+# Generate a unique filename from TEMPLATE by appending a random number to
+# the end. 
+#
+# If optional 2nd arg CREATEP is non-null, file will be created atomically
+# before returning.  This is to avoid the race condition that in between
+# the time that the temporary name is returned and the caller uses it,
+# someone else creates the file. 
+#:end docstring:
+
+###;;;autoload
+function mktmp ()
+{
+    local template="$1"
+    local tmpfile="${template}${RANDOM}"
+    local createp="$2"
+    local noclobber_status
+
+    case "$-" in
+    *C*)	noclobber_status=set;;
+    esac
+
+    if [ "${createp:+set}" = "set" ]; then
+       # Version which creates file atomically through noclobber test.   
+       set -o noclobber
+       (> "${tmpfile}") 2> /dev/null
+       while [ $? -ne 0 ] ; do
+          # Detect whether file really exists or creation lost because of
+          # some other permissions problem.  If the latter, we don't want
+          # to loop forever.
+          if [ ! -e "${tmpfile}" ]; then
+             # Trying to create file again creates stderr message.
+             echo -n "mktmp: " 1>&2
+             > "${tmpfile}"
+             return 1
+          fi
+          tmpfile="${template}${RANDOM}"
+          (> "${tmpfile}") 2> /dev/null
+       done
+       test "${noclobber_status}" != "set" && set +o noclobber
+    else
+       # Doesn't create file, so it introduces race condition for caller. 
+       while [ -e "${tmpfile}" ]; do
+          tmpfile="${template}${RANDOM}"
+       done
+    fi
+
+    echo "${tmpfile}"
+}
+
+provide mktmp
+
+# mktmp.bash ends here