Re: Supressing error messages on serial port open in Linux

The code that produces the unwanted message is in SerialPort.pm:

    # get the current attributes
    $ok = $self->{TERMIOS}->getattr($self->{FD});

    unless ( $ok ) {
        carp "can't getattr: $!";
        undef $self;
        return undef;
    }
[download]

So either comment out the carp ... line, or (if you don't want to mess with the module's source) overwrite the carp routine that has been imported into the Device::SerialPort namespace. I.e., in your code, before you call the constructor, say

{
  no warnings 'redefine';
  sub Device::SerialPort::carp { };  # no-op
}

...
    $PortObj = new Device::SerialPort($port, 1) or next;
[download]

The latter is somewhat of a dirty hack, because it of course also disables any carp messages that you might actually want to see...

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Re^2: Supressing error messages on serial port open in Linux by Corion (Patriarch) on Sep 02, 2011 at 12:57 UTC
`{ no warnings 'redefine'; sub Device::SerialPort::carp { }; # no-op }` [download] Please don't do it that way. Always localize the overwriting of subroutines: `{ no warnings 'redefine'; local *Device::SerialPort::carp = sub { # no-op }; $PortObj = new Device::SerialPort($port, 1) or next; } # carp works again` [download]	[reply] [d/l] [select]
Re^3: Supressing error messages on serial port open in Linux by pashanoid (Scribe) on Sep 05, 2011 at 05:31 UTC
Works great! Error messages are goner! Thank you!	[reply]
Re^3: Supressing error messages on serial port open in Linux by pashanoid (Scribe) on Sep 05, 2011 at 05:52 UTC
Ooops, now I'm getting this error: `Name "Device::SerialPort::carp" used only once: possible typo at dial. +pl line 58.` [download] This is my code: `eval "use Device::SerialPort; 1" or die $@; my $directory = '/dev'; opendir (DIR, $directory) or die $!; while (my $file = readdir(DIR)) { #print "$file\n"; push (@ports, "$directory/$file") if ($file =~ /ttyS/g); push (@ports, "$directory/$file") if ($file =~ /ttyUSB/g); } closedir(DIR); foreach my $port (@ports){ no warnings 'redefine'; local *Device::SerialPort::carp = sub {}; $PortObj = new Device::SerialPort($port, 1) or next; $PortObj->close; push(@ok_ports, $port); sleep (1); };` [download]	[reply] [d/l] [select]
Re^4: Supressing error messages on serial port open in Linux by Corion (Patriarch) on Sep 05, 2011 at 07:06 UTC
This is a warning, not an error. See diagnostics. You can suppress that warning by disabling the warning: `no warnings 'once';` [download]	[reply] [d/l]