Hi. I am wanting to do a non blocking type of read of the console input. I am trying to established a timed loop that performs as such that. The input response is only to indicate the operators wish to exit (the looping).

I am using Win 10 and Perl version 5.32.

From the web I get the following program as a possible approach;

use strict;
use warnings;

use Time::HiRes qw(usleep);

print "start\n";
usleep(2000000);
print "finish\n";

use Term::ReadKey;
ReadMode 4; # Turn off controls keys   4  or  "raw"
my $key;
while (not defined ($key = ReadKey(-1))) {
    # No key yet
    print ".";
    usleep(2000000);
}
print "Get key $key\n";
ReadMode 0; # Reset tty mode before exiting

[download]

The console output is;

start
finish
GetConsoleMode failed, LastError=|6| at C:/Strawberry/perl/vendor/lib/
+Term/ReadKey.pm line xxx.

[download]

The execution failure above is on ReadMode 4.

Are there any thoughts on why this failure occurs ?? I am surprised at the difficulty of achieving a non-blocking IO request and the lack of setting of say, a timeout of 0.

Regards JC.....

In reply to Non blocking read from the console by jmClifford

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