Date: Sat, 27 Sep 1997 16:42:50 +0200 From: j@uriah.heep.sax.de (J Wunsch) To: hackers@FreeBSD.ORG Subject: Re: Timeout for sh(1) 'read' ?? Message-ID: <19970927164250.YQ59393@uriah.heep.sax.de> In-Reply-To: <19970927163558.WP09379@uriah.heep.sax.de>; from J Wunsch on Sep 27, 1997 16:35:58 %2B0200 References: <199709260748.RAA00456@word.smith.net.au> <19970927163558.WP09379@uriah.heep.sax.de>
next in thread | previous in thread | raw e-mail | index | archive | help
I wrote:
> TMOUT If set to a value greater than zero, TMOUT
> will be the default timeout value for the
> read built-in command. The select compound
> command terminates after TMOUT seconds when
> input is from a terminal. Otherwise, the
> shell will terminate if a line is not
> entered within the prescribed number of sec-
> onds while reading from a terminal.
NB: pdksh only implements the last of the three features (at least my
version)...
> read [ -Aprs ] [ -d delim] [ -t timeout] [ -u
> unit] [ vname?prompt ] [ vname ... ]
...nor does it support -t timeout.
Adding -t timeout seems to be the best way to me. ${TMOUT} is just
confusing given the multitude of things it's going to do.
Btw., if you're going to do this, please do also implement -r. It
seems to be mandated by Posix.2:
By default, unless the -r option is specified, backslash (\) shall act as
an escape character, as described in 3.2.1.
<snip>
3.2.1 Escape Character (Backslash)
A backslash that is not quoted shall preserve the literal value of the
following character, with the exception of a <newline>. If a <newline>
follows the backslash, the shell shall interpret this as line
continuation. The backslash and <newline> shall be removed before
splitting the input into tokens.
(That is, the backslash should act like ^V.)
--
cheers, J"org
joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19970927164250.YQ59393>