Hi,

I would like to grab a Linux input-device via the EVIOCGRAB-ioctl call.

This is what's in my /usr/include/linux/input.h: 

#define EVIOCGRAB               _IOW('E', 0x90, int)                  
+  /* Grab/Release device */

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So I tried the naive approach first: 
open my $dev, "<", "/dev/input/event14" or die $!;
my $r = ioctl $dev, 0x90, 1;
print "$!\n" unless defined $r;

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But that prints "Invalid argument".

So then I generated the ph-files (they were not generated when I installed perl via perlbrew) with h2ph and ran it like this: 

require "linux/input.ph";

open my $dev, "<", "/dev/input/event14" or die $!;
my $r = ioctl $dev, EVIOCGRAB(), 1;
print "$!\n" unless defined $r;

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But this again results in "Invalid argument".

So how do I do this?

I am running 5.18.1 on Debian testing.

In reply to How to do ioctl? by morgon

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