Re: speed up gnulib-tool a bit

[Eric Blake]

Bruno Haible <bruno <at> clisp.org> writes:

> 
> > To be safe, I think you 
> > need to `exec <$file', or, restoring stdin, something like this:
> >   exec 5<&1 <$file
> >   while read r
> >   do
> >     $whatever
> >   done
> >   exec <&5 5<&-
> 
> Astonishing. I never saw this kind of low-level shell programming.
> Applied; see attached patch.
> 
...
> "$tmp"/added-files
> !   { # Rearrange file descriptors. Needed because "while ... done < ..."
> !     # constructs are executed in a subshell e.g. by Solaris 10 /bin/sh.
> !     exec 5<&1 < "$tmp"/added-files
> !     while read g f; do
> !       func_add_or_update
> !     done
> !     exec 1<&5 5<&-

Wait a minute.  You are reassigning and restoring stdout for the duration of 
the func_add_or_update, not stdin, thus leaving stdin open on a temp file.  As 
a result, platforms like cygwin where a directory cannot be deleted while a 
file is still open within that directory are now ALWAYS producing a warning 
along these lines:

$ gnulib-tool --update
...
Don't forget to
  - add "gnu/Makefile" to AC_CONFIG_FILES in ./configure.ac,
  - mention "gnu" in SUBDIRS in Makefile.am,
  - mention "-I ltdl/m4" in ACLOCAL_AMFLAGS in Makefile.am,
  - invoke M4_EARLY in ./configure.ac, right after AC_PROG_CC,
  - invoke M4_INIT in ./configure.ac.
rm: cannot remove directory `/tmp/gljj4484': Directory not empty
$

I'm applying this as the obvious fix.

2006-09-25  Eric Blake  <address@hidden>

        * gnulib-tool (func_import, func_create_testdir): Fix typos in
        2006-09-18 patch.

Index: gnulib-tool
===================================================================
RCS file: /sources/gnulib/gnulib/gnulib-tool,v
retrieving revision 1.172
diff -u -r1.172 gnulib-tool
--- gnulib-tool 22 Sep 2006 15:43:18 -0000      1.172
+++ gnulib-tool 25 Sep 2006 21:17:17 -0000
@@ -1691,11 +1691,11 @@
     | sed -e "s,^.*\$,&$delimiter&," -e "$sed_rewrite_new_files" 
> "$tmp"/added-files
   { # Rearrange file descriptors. Needed because "while ... done < ..."
     # constructs are executed in a subshell e.g. by Solaris 10 /bin/sh.
-    exec 5<&1 < "$tmp"/added-files
+    exec 5<&0 < "$tmp"/added-files
     while read g f; do
       func_add_or_update
     done
-    exec 1<&5 5<&-
+    exec <&5 5<&-
   }
   # Then the files that are in new-files and in old-files:
   already_present=true
@@ -1704,11 +1704,11 @@
     | sed -e "s,^.*\$,&$delimiter&," -e "$sed_rewrite_new_files" > "$tmp"/kept-
files
   { # Rearrange file descriptors. Needed because "while ... done < ..."
     # constructs are executed in a subshell e.g. by Solaris 10 /bin/sh.
-    exec 5<&1 < "$tmp"/kept-files
+    exec 5<&0 < "$tmp"/kept-files
     while read g f; do
       func_add_or_update
     done
-    exec 1<&5 5<&-
+    exec <&5 5<&-
   }
 
   # Command-line invocation printed in a comment in generated gnulib-cache.m4.
@@ -2099,7 +2099,7 @@
     > "$tmp"/files
   { # Rearrange file descriptors. Needed because "while ... done < ..."
     # constructs are executed in a subshell e.g. by Solaris 10 /bin/sh.
-    exec 5<&1 < "$tmp"/files
+    exec 5<&0 < "$tmp"/files
     while read g f; do
       func_lookup_file "$f"
       if test -n "$lookedup_tmp"; then
@@ -2113,7 +2113,7 @@
         fi
       fi
     done
-    exec 1<&5 5<&-
+    exec <&5 5<&-
   }
 
   # Create $sourcebase/Makefile.am.