* doc/autoconf.texi (Shell Substitutions) <${10}>: Document
a pitfall with $10.
Signed-off-by: Eric Blake <ebl...@redhat.com>
---
ChangeLog | 6 ++++++
doc/autoconf.texi | 12 ++++++++++++
2 files changed, 18 insertions(+), 0 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 14abf51..1fca7bb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2011-05-05 Eric Blake <ebl...@redhat.com>
+
+ doc: document dash bug with positional parameters
+ * doc/autoconf.texi (Shell Substitutions) <${10}>: Document
+ a pitfall with $10.
+
2011-04-27 Eric Blake <ebl...@redhat.com>
docs: document NetBSD join bug
diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index b466e56..7ff693f 100644
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -15846,6 +15846,18 @@ Shell Substitutions
bad substitution
@end example
+Conversely, not all shells obey the Posix rule that when braces are
+omitted, multiple digits beyond a @samp{$} imply the single-digit
+positional parameter expansion concatenated with the remaining literal
+digits. To work around the issue, you must use braces.
+
+@example
+$ @kbd{bash -c 'set a b c d e f g h i j; echo $10 $@{1@}0'}
+a0 a0
+$ @kbd{dash -c 'set a b c d e f g h i j; echo $10 $@{1@}0'}
+j a0
+@end example
+
@item $@{@var{var}:-@var{value}@}
@c Info cannot handle `:' in index entries.
@ifnotinfo
--
1.7.4.4
