Re: [tobias.rehb...@web.de: Re: [OT] C programming question: reopen stdin]
2009/4/16 Tobias Rehbein tobias.rehb...@web.de: s/Good/Could/ -- Forwarded message -- From: Tobias Rehbein tobias.rehb...@web.de To: Mel Flynn mel.flynn+fbsd.questi...@mailing.thruhere.net Date: Thu, 16 Apr 2009 21:03:52 +0200 Subject: Re: [OT] C programming question: reopen stdin Am Tue, Apr 14, 2009 at 09:07:26PM +0200 schrieb Mel Flynn: On Tuesday 14 April 2009 20:13:00 Tobias Rehbein wrote: I'm having a little trouble solving a specific problem in C. I want to write a filter which reads data from stdin. After reading the user should be able to interact with the program via stdin. Just open(2) /dev/tty. If tty is invalid, then you don't have to expect a user either. Thanks for this hint. I tried to implement an example. Good someone take a look at it and tell me if I did it right. Well, at least it works... The code is here: http://gist.github.com/95320 To avoid further spamming of the freebsd-questions mailing list: Could someone point me to a good place to ask C programming questions? Regards Tobias ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org http://groups.google.com/group/comp.lang.c The oldest and probably most populated. -- A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail? ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: [OT] C programming question: reopen stdin
Am Tue, Apr 14, 2009 at 09:07:26PM +0200 schrieb Mel Flynn: On Tuesday 14 April 2009 20:13:00 Tobias Rehbein wrote: I'm having a little trouble solving a specific problem in C. I want to write a filter which reads data from stdin. After reading the user should be able to interact with the program via stdin. Just open(2) /dev/tty. If tty is invalid, then you don't have to expect a user either. Thanks for this hint. I tried to implement an example. Good someone take a look at it and tell me if I did it right. Well, at least it works... The code is here: http://gist.github.com/95320 To avoid further spamming of the freebsd-questions mailing list: Could someone point me to a good place to ask C programming questions? Regards Tobias ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
[tobias.rehb...@web.de: Re: [OT] C programming question: reopen stdin]
s/Good/Could/ ---BeginMessage--- Am Tue, Apr 14, 2009 at 09:07:26PM +0200 schrieb Mel Flynn: On Tuesday 14 April 2009 20:13:00 Tobias Rehbein wrote: I'm having a little trouble solving a specific problem in C. I want to write a filter which reads data from stdin. After reading the user should be able to interact with the program via stdin. Just open(2) /dev/tty. If tty is invalid, then you don't have to expect a user either. Thanks for this hint. I tried to implement an example. Good someone take a look at it and tell me if I did it right. Well, at least it works... The code is here: http://gist.github.com/95320 To avoid further spamming of the freebsd-questions mailing list: Could someone point me to a good place to ask C programming questions? Regards Tobias ---End Message--- ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: [OT] C programming question: reopen stdin
On Thursday 16 April 2009 21:03:52 Tobias Rehbein wrote:
Am Tue, Apr 14, 2009 at 09:07:26PM +0200 schrieb Mel Flynn:
On Tuesday 14 April 2009 20:13:00 Tobias Rehbein wrote:
I'm having a little trouble solving a specific problem in C. I want to
write a filter which reads data from stdin. After reading the user
should be able to interact with the program via stdin.
Just open(2) /dev/tty. If tty is invalid, then you don't have to expect a
user either.
Thanks for this hint. I tried to implement an example. Good someone take a
look at it and tell me if I did it right. Well, at least it works...
The code is here:
http://gist.github.com/95320
It is really much simpler, see below for code:
% cat tty.c | ./tty
1: #include stdio.h
1: #include err.h
snip
Hello!
2: Hello!
quit
(Don't focus on the 80char linebuf, I just know for this example I don't need
more).
/dev/tty is the controlling terminal input. Stdin is the standard input,
which is either the receiving end of a pipe/redirection or the controlling
terminal in it's absence.
To avoid further spamming of the freebsd-questions mailing list: Could
someone point me to a good place to ask C programming questions?
O'Reilly has a few good titles (Practical C programming is a good primer,
followed by Algorithms with C), other then that, comp.lang.c newsgroup.
--
Mel
#include stdio.h
#include err.h
int main(int argc, char **argv)
{
FILE *tty;
char linebuf[80];
while( fgets(linebuf, sizeof(linebuf), stdin) )
printf(1: %s, linebuf);
if( (tty = fopen(/dev/tty, r)) == NULL )
errx(0, Running non-interactively. See ya!);
while( fgets(linebuf, sizeof(linebuf), tty) )
{
if( strcmp(linebuf, quit\n) == 0 )
break;
printf(2: %s, linebuf);
}
return 0;
}
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Re: [OT] C programming question: reopen stdin
On Tuesday 14 April 2009 20:13:00 Tobias Rehbein wrote: I'm having a little trouble solving a specific problem in C. I want to write a filter which reads data from stdin. After reading the user should be able to interact with the program via stdin. Just open(2) /dev/tty. If tty is invalid, then you don't have to expect a user either. -- Mel ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
