See <http://lists.gnu.org/archive/html/bug-patch/2015-06/msg00009.html>

From 0507dfad5f060161f01840067e1bb1615257b636 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= <ludo@gnu.org>
Date: Mon, 8 Jun 2015 17:27:56 +0200
Subject: [PATCH] Do not rely on PATH_MAX when reading a symlink target.

* src/util.c (move_file, copy_file): Use 'fromst->st_size + 1' and
'tost->st_size + 1' for the allocation, and 'fromst->st_size' and
'tost->st_size' instead of PATH_MAX.  Fixes compilation on GNU/Hurd.
---
 src/util.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/util.c b/src/util.c
index 1cc08ba..67dbd3a 100644
--- a/src/util.c
+++ b/src/util.c
@@ -460,12 +460,12 @@ move_file (char const *from, bool *from_needs_removal,
 
 	  /* FROM contains the contents of the symlink we have patched; need
 	     to convert that back into a symlink. */
-	  char *buffer = xmalloc (PATH_MAX);
+	  char *buffer = xmalloc (fromst->st_size + 1);
 	  int fd, size = 0, i;
 
 	  if ((fd = safe_open (from, O_RDONLY | O_BINARY, 0)) < 0)
 	    pfatal ("Can't reopen file %s", quotearg (from));
-	  while ((i = read (fd, buffer + size, PATH_MAX - size)) > 0)
+	  while ((i = read (fd, buffer + size, fromst->st_size - size)) > 0)
 	    size += i;
 	  if (i != 0 || close (fd) != 0)
 	    read_fatal ();
@@ -610,10 +610,10 @@ copy_file (char const *from, char const *to, struct stat *tost,
 
   if (S_ISLNK (mode))
     {
-      char *buffer = xmalloc (PATH_MAX + 1);
+      char *buffer = xmalloc (tost->st_size + 1);
       ssize_t r;
 
-      if ((r = safe_readlink (from, buffer, PATH_MAX)) < 0)
+      if ((r = safe_readlink (from, buffer, tost->st_size)) < 0)
 	pfatal ("Can't read %s %s", "symbolic link", from);
       buffer[r] = '\0';
       if (safe_symlink (buffer, to) != 0)
-- 
2.16.2

e='range'>range</option>
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<div class='path'>path: <a href='/guix/log/?id=b610e4b9a7d4423603cac1da4f16475fb1e03e83'>root</a>/<a href='/guix/log/etc?id=b610e4b9a7d4423603cac1da4f16475fb1e03e83'>etc</a>/<a href='/guix/log/etc/indent-code.el?id=b610e4b9a7d4423603cac1da4f16475fb1e03e83'>indent-code.el</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/etc/indent-code.el?id=b610e4b9a7d4423603cac1da4f16475fb1e03e83&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-08-18 23:54:55 +0200'>2020-08-18</span></td><td><a href='/guix/commit/etc/indent-code.el?id=275e66b8b47a6e085a6f359b69af424bc9f6b13d'>etc: indent-code.el: Match not only ‘(define-public’.</a><span class='msg-avail'>...<span class='msg-tooltip'>* etc/indent-code.el (main): Also match ‘(define’, as intended.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-05-14 23:05:42 -0400'>2020-05-14</span></td><td><a href='/guix/commit/etc/indent-code.el?id=cb21ae76714f1873d3b3fb40d5135f00ec104b85'>etc: indent-code.el: Use the --quick option.</a><span class='msg-avail'>...<span class='msg-tooltip'>This prevents Emacs from loading the autoload definitions found in its
profile, which needlessly clutters the output.  It also prevents Geiser (if
installed) from blocking the script and asking the user to input the Scheme
implementation to use.

The trick for passing multiple arguments to Emacs is to use what is called a
"sesquicolon" (see https://www.emacswiki.org/emacs/EmacsScripts).

* etc/indent-code.el.in: Rename to...
* etc/indent-code.el: ...this.  Adapt the shebang to use a sesquicolon, and
pass the --quick option to Emacs.  Since this line is interpreted by the
shell, simply use Emacs from the PATH instead of from a hard coded location.
(main): New procedure, used as the entry point.
* configure.ac: Remove the warning about Emacs.  Emacs can now be installed
any time by the user if they want to use the script.
* .gitignore: No longer ignore changes to etc/indent-code.el.
</span></span></td><td>Maxim Cournoyer</td></tr>