From: cgf AT cygnus DOT com (Christopher G. Faylor)
Subject: Patch to fix "excessive bash delays"
23 Aug 1998 19:37:40 GMT
Message-ID: <6rpr24$t2u$1@cronkite.cygnus.com>
X-Newsreader: trn 4.0-test63 (15 March 1998)

I did some digging around today to determine where bash
was adding an extra '/' when HOME=='/'.  The patch below
should solve a couple of such instances.

Adding an extra '/' to the beginning of a file name is
problematic for Windows because it causes Windows to
interpret the filespec as a network share, which means
that accessing the file can result in excessive delays.

This was most noticeable if a cygwin user did not have a
/etc/passwd file causing bash to set the HOME environment
variable to '/'.  In this scenario, bash would look for things
like: '//.bashrc' and '//.bash_history'.  Most annoyingly it
also periodically checks the file
'<current_directory>/unknown/I have no name!' for mail.  If
the <current_directory> is '/' then this will revert to
'//unknown/I have no name!'.

So, a work around for this problem is to either set up
an /etc/passwd file or explicitly set HOME to some directory
besides '/'.  Additionally, the MAIL_CHECK variable should
be 'unset'.  Or, you can apply the patch below to bash and
rebuild bash.exe

This patch is against Cygnus's version of 2.02.0.  I don't
know if it will patch cleanly against any other version.

Index: general.c
===================================================================
RCS file: /cvs/cvsfiles/devo/bash/general.c,v
retrieving revision 1.3
diff -u -p -r1.3 general.c
--- general.c	1998/06/11 04:32:40	1.3
+++ general.c	1998/08/23 19:15:34
@@ -742,7 +742,8 @@ full_pathname (file)
       return ((char *)NULL);
     }
   dlen = strlen (current_dir);
-  current_dir[dlen++] = '/';
+  if (dlen > 1)
+    current_dir[dlen++] = '/';
 
   /* Turn /foo/./bar into /foo/bar. */
   if (file[0] == '.' && file[1] == '/')
Index: lib/readline/tilde.c
===================================================================
RCS file: /cvs/cvsfiles/devo/bash/lib/readline/tilde.c,v
retrieving revision 1.3
diff -u -p -r1.3 tilde.c
--- tilde.c	1998/06/11 04:33:17	1.3
+++ tilde.c	1998/08/23 19:15:34
@@ -232,11 +232,14 @@ tilde_expand (string)
       free (tilde_word);
 
       len = strlen (expansion);
-      if ((result_index + len + 1) > result_size)
-	result = xrealloc (result, 1 + (result_size += (len + 20)));
+      if (len > 1 || *expansion != '/' || *string != '/')
+	{
+	  if ((result_index + len + 1) > result_size)
+	    result = xrealloc (result, 1 + (result_size += (len + 20)));
 
-      strcpy (result + result_index, expansion);
-      result_index += len;
+	  strcpy (result + result_index, expansion);
+	  result_index += len;
+	}
       free (expansion);
     }
 
-- 
cgf AT cygnus DOT com             "Everything has a boolean value, if you stand
http://www.cygnus.com/      far enough away from it."  -- Galena Alyson Canada