[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH 6/6] use print or printf or cat as $ECHO
From: |
Paolo Bonzini |
Subject: |
Re: [PATCH 6/6] use print or printf or cat as $ECHO |
Date: |
Tue, 11 Nov 2008 07:06:58 +0100 |
User-agent: |
Thunderbird 2.0.0.17 (Macintosh/20080914) |
> Who guarantees you that ksh supplies TMOUT? OTOH, TMOUT is not in any
> way restricted, so a user (more likely: a sysadmin) could set and export
> it, and reasonably so: every Posix shell understands it, bash included.
I tested that both ksh and pdksh set TMOUT = 0 at startup, for example:
$ ksh
[033]0;h - w007]h:w u$ unset TMOUT
[033]0;h - w007]h:w u$ ksh -c "echo \$TMOUT"
0
bash, zsh, ash/dash do not.
> And since when are 2 forks a suitable tradeoff for portability?
It's just a guard to avoid unnecessary tests, like
test "${TMOUT+set}" = set && (...) 2>/dev/null
It's not affecting portability.
> Should we document $TMOUT as a reliable way to detect ksh, the way we already
> use {BASH,ZSH}_VERSION as reliable witnesses of those two shells?
Maybe; in any case, if we aren't saying it already we should point out
that they can be exported and this affects the tests.
Paolo