From 949e49297940529d2803a274617af8951f18e82b Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Thu, 21 Jul 2022 12:49:50 -0700 Subject: [PATCH] basename and dirname are portable now * doc/autoconf.texi (Limitations of Usual Tools): basename and dirname are portable shell commands now. --- doc/autoconf.texi | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) diff --git a/doc/autoconf.texi b/doc/autoconf.texi index fdc662e1..fa5a9f48 100644 --- a/doc/autoconf.texi +++ b/doc/autoconf.texi @@ -14065,6 +14065,9 @@ Output the directory portion of @var{file-name}. For example, if @code{$file} is @samp{/one/two/three}, the command @code{dir=`AS_DIRNAME(["$file"])`} sets @code{dir} to @samp{/one/two}. +@code{AS_DIRNAME} was designed long ago when +the @command{dirname} command was not universally supported. +Nowadays one can safely use @code{dir=`dirname -- "$file"`} instead. This interface may be improved in the future to avoid forks and losing trailing newlines. @end defmac @@ -19139,8 +19142,13 @@ of at most 3070 bytes. @item @command{basename} @c --------------------- @prindex @command{basename} -Not all hosts have a working @command{basename}. -You can use @command{expr} instead. +Long ago some hosts lacked a working @command{basename}, +and portable scripts needed to use @command{expr} instead. +Nowadays it is safe to use @command{basename}. For example: + +@example +base=`basename -- "$file"` +@end example @c AS_BASENAME is to be replaced by a better API. @ignore @@ -19331,12 +19339,13 @@ Some implementations, such as Tru64's, fail when comparing to @item @command{dirname} @c -------------------- @prindex @command{dirname} -Not all hosts have a working @command{dirname}, and you should instead -use @code{AS_DIRNAME} (@pxref{Programming in M4sh}). For example: +Long ago some hosts lacked a working @command{dirname} and portable +scripts needed to use use @code{AS_DIRNAME} (@pxref{Programming in M4sh}). +Nowadays @command{dirname} suffices and the following are equivalent: @example -dir=`dirname "$file"` # This is not portable. -dir=`AS_DIRNAME(["$file"])` # This is more portable. +dir=`dirname -- "$file"` +dir=`AS_DIRNAME(["$file"])` @end example -- 2.34.1