On 1/30/15 2:09 PM, Jonathan Hankins wrote:
> A test with the POSIX S_ISREG macro on HISTFILE will determine if it, or
> the file it points to in the case of a symlink, is a regular file.
>
> Just looked through the source, and it looks like general.c:file_exists()
> does not do any special handling of non-regular files, and
> lib/readline/histfile.c:history_do_write() calls open() and rename() on
> HISTFILE without checking if it is a non-regular file, which I imagine
> could lead to various "bad things" in the case of pipes, char and block
> devices, etc. such as what the OP pointed about about "/dev/null".
Well, like always, it depends. The current implementation allows a user
to use a named pipe with a different program running to be a `history
file'. That flexibility can be valuable.
I don't think that readline should be attempting to do backups of non-
regular files, though. The history file truncation code, which is called
when HISTFILESIZE is changed, already rejects attempts to use non-regular
files.
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU [email protected] http://cnswww.cns.cwru.edu/~chet/
