* doc/autoconf.texi (Limitations of Builtins): Comment `true'.

diff --git a/ChangeLog b/ChangeLog
index bb53cf420ab83600360d0fd9f346df6948bb305c..8536b9f9050d2d4d7fe067d0ce1c0e3e5286df33 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2000-11-14  Akim Demaille  <akim@epita.fr>
+
+       * doc/autoconf.texi (Limitations of Builtins): Comment `true'.
+
 2000-11-14  Akim Demaille  <akim@epita.fr>
 
        * BUGS: New file.

diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index 55145be4881eb1e3048d82169d0f2eb3625a11df..2f5f1fce4e2687591b07a67eab5d88970d3365a2 100644 (file)
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -5701,6 +5701,22 @@ $ exit
 @noindent
 Fortunately this bug affects only trap.
 
+@item @command{true}
+@cindex @command{true}
+@cindex @command{:}
+Don't worry: as far as we know @command{true} is portable.
+Nevertheless, it's not always a builtin (e.g., Bash 1.x), and the
+portable shell community tends to prefer using @command{:}.  This has an
+funny side effect: when asked whether @command{false} is more portable
+than @command{true} Alexandre Oliva answered
+
+@quotation
+In a sense, yes, because if it doesn't exist, the shell will produce an
+exit status of failure, which is correct for @command{false}, but not
+for @command{true}.
+@end quotation
+
+
 @item @command{unset}
 @cindex @command{unset}
 You cannot assume the support of @command{unset}, nevertheless, because