Re: tail.c: 836: recheck: Assertion `valid_file_spec (f)' failed (linux, kernel 2.4.x, coreutils 5.2.1)

[Jim Meyering]

Roberto Nibali <address@hidden> wrote:
...
>> Oh.  I see that this has been fixed since 5.2.1.
...
> Hmmm, has it really? Could you show me the changeset, please?

My use of `since' was misleading.
This was fixed *after* coreutils-5.2.1.

>> You can find the development version here:
>>   http://savannah.gnu.org/cvs/?group=coreutils

Here's one of the related ChangeLog entries:

2004-07-23  Paul Eggert  <address@hidden>

        Fix bug with "tail -f" reported by Rob Holland in
        <http://lists.gnu.org/archive/html/bug-coreutils/2004-07/msg00054.html>.
        Also, remove the undocumented and unsupported-since-2000
        --max-consecutive-size-changes options.  Fix another related bug:
        "tail" got confused if stdin, stdout, or stderr were closed.
        Also, use output buffering even with "tail -f".

        * NEWS: Document this, plus yesterday's patch.
        * doc/coreutils.texi (tail invocation): "size has remained the same"
        -> "file has not changed", which is more accurate for fifos.
        * src/tail.c: Include fcntl-safer.h.
        (COPY_TO_EOF): Set to UINTMAX_MAX, not OFF_T_MAX (which was wrong).
        (COPY_A_BUFFER): New macro.
        (struct File_spec): New members mtime, mode, blocking.
        Remove member n_consecutive_size_changes.
        (DEFAULT_MAX_N_CONSECUTIVE_SIZE_CHANGES,
        max_n_consecutive_size_changes_between_opens,
        MAX_CONSECUTIVE_SIZE_CHANGES_OPTION): Remove.
        (long_options, tail_forever, parse_options):
        Remove (non-)support for --max-consecutive-size-changes.
        (record_open_fd): New function.
        (recheck, tail_file): Use it.  Don't assume that stdin is open.
        (dump_remainder): Add support for new COPY_A_BUFFER special value.
        Treat errno==EAGAIN like EOF, since it might be a nonblocking read.
        (recheck): New arg BLOCKING, specifying whether to use blocking reads.
        All uses changed.
        (n_live_files): Remove, replacing with...
        (any_live_files): New function.  All uses changed.
        (tail_forever): Use nonblocking I/O unless we know that blocking I/O
        is safe; this avoids some hangs when reading from a fifo.
        Avoid invoking fstat or sleep when using blocking I/O.
        Do not check for changes to size if the file is not a regular file,
        as the size is undefined in that case.
        Check for changes to mtime or mode, too; this works for non-regular
        files.
        (tail_forever, main): Redo fflush strategy to work even when input
        is nonblocking.  Don't use unbuffered output; just flush when needed.