Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!cse!texas!harrison
From: harrison@csl.dl.nec.com (Mark Harrison)
Newsgroups: comp.lang.perl
Subject: can't get ioctl value
Message-ID: <1991May15.003413.22693@csl.dl.nec.com>
Date: 15 May 91 00:34:13 GMT
Organization: NEC America, C & C Software Development Laboratory
Lines: 42

I am having a problem getting the value needed for an TIOCGWINSZ (get
window size) ioctl.  If I hardcode the value printed by the C program,
everything works correctly.  I have run "h2ph * */*" in /usr/include.

Anybody have a clue?  Thanks in advance!

C program:
> #include <sys/ioccom.h>
> #include <sys/ttycom.h>
> main(){printf("%d\n", TIOCGWINSZ);}

from ioccom.ph:
>   eval 'sub _IOR {
>       local($x,$y,$t) = @_;
>       eval "( &_IOC_OUT|(($sizeof{$t}& &_IOCPARM_MASK)<<16)|(ord(\'$x\')<<8)|$y)";
>   }';

from ttycom.ph:
>     eval 'sub TIOCGWINSZ { &_IOR("t", 104, struct winsize);}';

My program:

#!/usr/local/bin/perl
require "sys/ioccom.ph";
require "sys/ttycom.ph";
$x = &TIOCGWINSZ;
print "x =", $x, ":\n";
print "TIOCGWINSZ =", &TIOCGWINSZ, ":\n";
ioctl(STDIN, &TIOCGWINSZ, $gettyval) || die "can't get window size";
#ioctl(STDIN, 1074295912, $gettyval); # <-- this one works ok.
($Rows, $Cols) = unpack("ss", $gettyval);
~

My output:
> x =:
> TIOCGWINSZ =:
> can't get window size at foo line 13.
-- 
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