Re^3: Telnet command with more than 1024 chars (updated)

Why don't you try to get the byte size of the command (145 characters) with Devel::Size or bytes.

By doing this you will now if you are exceeding the maxim transmission size (1,048,576 bytes) see the documentation from the module Net::Telnet for max_buffer_length - maximum size of input buffer.

I am not only suggesting to use ssh because you will avoid all these problems, I am suggesting it because of many many reasons. Read an short article about the comparison Telnet & SSH.

Hope this helps, BR.

Seeking for Perl wisdom...on the process of learning...not there...yet!

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Re^4: Telnet command with more than 1024 chars (updated) by ElectricCheese (Initiate) on Jul 25, 2017 at 19:49 UTC
Hello thanos1983! Well, I decided to use a different approach instead of using `$t->print` and `$t->waitfor`, I decided to use line continuation character, and I discovered it worked very well! I found this code here and adapted for my needs, on which it fitted well. There says some shells have a limitation of 255 characters line limit. sub cmd_unixlong { my ($obj, $cmd) = @_; my ($line, $pos); my $max_tty_line = 254; ## Start a Bourne shell. $obj->cmd(-string => "/usr/bin/env " . "'PS1=<xPROMPTx> ' 'PS2=<xPROMPTx> ' /bin/sh -i", -prompt => '/<xPROMPTx> $/') or return; ## Break-up the one large command line and send as shorter lin +es. $pos = 0; while (1) { $line = substr $cmd, $pos, $max_tty_line; $pos += length $line; last unless $pos < length $cmd; ## Send the line with continuation char. $obj->cmd(-string => "$line\\", -prompt => '/<xPROMPTx> $/') or return; } ## Send the last line and return the output. $obj->cmd("$line ; exit"); } # end sub cmd_unixlong [download] I'm still using telnet, so I changed it to something more or less like this: `sub cmd_telnetlong { my ($obj, $cmd) = @_; my ($line, $pos); my $max_tty_line = 254; ## Break-up the one large command line and send as shorter lin +es. $pos = 0; while (1) { $line = substr $cmd, $pos, $max_tty_line; $pos += length $line; last unless $pos < length $cmd; ## Send the line with continuation char. $obj->cmd(-string => "$line^", -prompt => '/More?/i') or return; } ## Send the last line and return the output. return $obj->cmd("$line ; exit"); } # end sub cmd_unixlong` [download] As I haven't found anything to solve the line limitation, this workaround served me very well! Thanks all for your time!	[reply] [d/l] [select]

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Re^4: Telnet command with more than 1024 chars (updated)
by ElectricCheese (Initiate) on Jul 25, 2017 at 19:49 UTC

Hello thanos1983!

Well, I decided to use a different approach instead of using $t->print and $t->waitfor, I decided to use line continuation character, and I discovered it worked very well! I found this code here and adapted for my needs, on which it fitted well. There says some shells have a limitation of 255 characters line limit.

sub cmd_unixlong {
        my ($obj, $cmd) = @_;
        my ($line, $pos);
        my $max_tty_line = 254;

        ## Start a Bourne shell.
        $obj->cmd(-string => "/usr/bin/env " .
                  "'PS1=<xPROMPTx> ' 'PS2=<xPROMPTx> ' /bin/sh -i",
                  -prompt => '/<xPROMPTx> $/')
            or return;

        ## Break-up the one large command line and send as shorter lin
+es.
        $pos = 0;
        while (1) {
            $line = substr $cmd, $pos, $max_tty_line;
            $pos += length $line;
            last unless $pos < length $cmd;

            ## Send the line with continuation char.
            $obj->cmd(-string => "$line\\",
                      -prompt => '/<xPROMPTx> $/')
                or return;
        }

        ## Send the last line and return the output.
        $obj->cmd("$line ; exit");

    } # end sub cmd_unixlong
[download]

sub cmd_telnetlong {
        my ($obj, $cmd) = @_;
        my ($line, $pos);
        my $max_tty_line = 254;

        ## Break-up the one large command line and send as shorter lin
+es.
        $pos = 0;
        while (1) {
            $line = substr $cmd, $pos, $max_tty_line;
            $pos += length $line;
            last unless $pos < length $cmd;

            ## Send the line with continuation char.
            $obj->cmd(-string => "$line^",
                      -prompt => '/More?/i')
                or return;
        }

        ## Send the last line and return the output.
        return $obj->cmd("$line ; exit");
    } # end sub cmd_unixlong
[download]

As I haven't found anything to solve the line limitation, this workaround served me very well! Thanks all for your time!

[reply]
[d/l]
[select]