Re: tail -f and tail --follow=name in pipe

[Jim Meyering]

Ernst Kloppenburg <address@hidden> wrote:
> I am using 'tail' from textutils 2.0-6 on a Debian GNU/Linux system.
>
> When tail is used in a pipe, it behaves strangely when the option
> --follow=name is given. The behaviour I found strange is illustrated by the
> following example:
>
> 1) tail -f /var/log/syslog | wc
>    when wc is terminated by kill <pid>, the tail program exits the next time
>    a line is written to the file followed. This makes sense, because at this
>    time it is detekted that the pipe is broken.
>
> 2) tail --follow=name /var/log/syslog | wc
>    in this case, when wc is killed, the tail command never terminates

Thanks for the report.
I can't reproduce that using the latest test release on the same
type of system.  Would you please try it?

  ftp://alpha.gnu.org/gnu/fetish/textutils-2.0.18.tar.gz
  ftp://ftp.funet.fi/pub/gnu/alpha/gnu/textutils/textutils-2.0.18.tar.gz

You may need this patch:

[!__BOUNDED_POINTERS__]: Define away __bounded, __unbounded, and __ptrvalue.
=============================================================================
Index: lib/regex.c
===================================================================
RCS file: /fetish/textutils/lib/regex.c,v
retrieving revision 1.75
retrieving revision 1.76
diff -u -p -u -r1.75 -r1.76
--- lib/regex.c 2001/11/27 21:34:15     1.75
+++ lib/regex.c 2001/12/02 17:46:54     1.76
@@ -112,6 +112,13 @@
 #  define gettext_noop(String) String
 # endif

+/* Support for bounded pointers.  */
+# ifndef __BOUNDED_POINTERS__
+#  define __bounded      /* nothing */
+#  define __unbounded    /* nothing */
+#  define __ptrvalue     /* nothing */
+# endif
+
 /* The `emacs' switch turns on certain matching commands
    that make sense only in Emacs. */
 # ifdef emacs