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From: halbert@halbert.crl.dec.com (Dan Halbert)
Newsgroups: comp.lang.perl
Subject: STDIN waits for ^D, not newline
Message-ID: <5249@crltrx.crl.dec.com>
Date: 8 May 90 22:40:51 GMT
Sender: news@crltrx.crl.dec.com
Reply-To: halbert@crl.dec.com
Organization: DEC Cambridge Research Lab
Lines: 32

(Using Perl version:
$Header: perly.c, v 3.0.1.4 90/02/28 18:06:41 lwall Locked $
Patch level: 15)

I'm writing an interactive terminal program in perl. It prompts the user
and reads from STDIN.

If you try this program:

print "prompt: ";
$a = <STDIN>;
print $a;

then a carriage return will end the input. (That is, <STDIN> will read
one line.)

However, if you try:

print "prompt: ";
local ($a) = <STDIN>;
print $a;

then STDIN keeps reading input until I type ^D.

In my program, the local() is in a subroutine, of course, but that isn't
necessary to reproduce the problem.

Opening "-" explicitly doesn't solve the problem.

I just started looking at comp.lang.perl; sorry if this is old hat.

--Dan Halbert