X-Git-Url: https://git.notmuchmail.org/git?p=notmuch;a=blobdiff_plain;f=configure;h=dc0dba4c12f5c93908b59c31b2b2dd589464ea87;hp=5602be247611558fdb1cc1f743e0ac3cf9239a82;hb=015bc16f5352e17cf203e90f2b8f37f3f4ea8c6e;hpb=fae97b1013a18ad960aa0cd413154783409f310d

diff --git a/configure b/configure
index 5602be24..dc0dba4c 100755
--- a/configure
+++ b/configure
@@ -1,7 +1,21 @@
 #! /bin/sh
 
+# Test whether this shell is capable of parameter substring processing.
+( option='a/b'; : ${option#*/} ) 2>/dev/null || {
+    echo "
+The shell interpreting '$0' is lacking some required features.
+
+To work around this problem you may try to execute:
+
+    ksh $0 $*
+ or
+    bash $0 $*
+"
+    exit 1
+}
+
 # Store original IFS value so it can be changed (and restored) in many places.
-readonly DEFAULT_IFS=$IFS
+readonly DEFAULT_IFS="$IFS"
 
 srcdir=$(dirname "$0")