how do i use s3270/x3270 for scripting

doomed9 · 11-05-2009, 10:11 AM

I'm trying to write a script which will (upon completion), navigate through records maintained on an IBM mainframe using a tn3270 terminal, and scrape said records into html files for later manipulation.

I've read http://x3270.bgp.nu/s3270-man.html

and http://x3270.bgp.nu/x3270-script.html

The latter states:

Quote:

Commands are emulator actions; the syntax is the same as for the right-hand side of an Xt translation table entry (an x3270 or c3270 keymap). Unlike translation tables, action names are case-insensitive, can be uniquely abbreviated, and the parentheses may be omitted if there are no parameters. Any input line that begins with # or ! is treaded as a comment and will be ignored.

So...

By that definition, the following should work:

Code:

connect(L:ssl3270.myhost.org:2023) \
ascii() \
string(command1) \
enter() \
ascii() \
enter() \
string(command2) \
ascii() \
pf(3) \
quit()

However, when i call the above using the script() function in s3270, the script prints to stdout, but the actions are not executed as expected.

For example:

Code:

(NOTICE: I've shortened the script for example's sake)
$ s3270
script(/path/to/my/script/test.3270)
connect(L:ssl3270.myhost.org:2023)
ascii()
string(command1)
enter()
ascii()

L U U N N 4 24 80 0 0 0x0 -
ok

Expected output would've been (for starters) the first character of the status string changing to U (as the keyboard should unlock when i am connected), and the initial screen printed in ascii, a command sent, and the resulting screen printed in ascii as well.

I'm not sure what i am doing wrong. Can someone give me an example script that works? Something simple that depicts how i can use something like bash, perl, or python to send commands to this application and navigate through screens.

Thanks in advance

doomed9 · 11-05-2009, 08:12 PM

So, i worked out how to do this in bash; though, i don't like the result.

Code:

#!/bin/bash
file_path="/path/to/my/files"
date=$(date +"%Y%m%d%H%M%S")
x3270if "connect(L:ssl3270.myhost.org:2023)"
x3270if "printtext(html,file,$file_path/myhost-$date.html)"
x3270if "string(command1)"
x3270if "enter"
x3270if "printtext(html,file,$file_path/myhost-$date.html)"
x3270if "enter"
x3270if "string(command2)"
x3270if "enter"

This is a bash script that, if called from within s3270, will navigate to the application login page and create html files of each page along the way.

while x3270if is nice, i reckon i expected a simpler solution...something easier to use with a language's built-in functionality.

What would i do with perl? Hopefully not make a call to system() each time i want to input data. Is there a way to treat the terminal connection as a file handle and just send commands to it via print()?

chrism01 · 11-06-2009, 02:18 AM

If you're keen on doing this in Perl, ask the gurus over at http://www.perlmonks.org/

doomed9 · 11-07-2009, 05:55 PM

Chris,

Thank you for the excellent referral. I was on the right track to my answer in a few minutes...

Using perl's IPC::Run module, i was able to pipe commands directly to the s3270 subprocess. Thus, the below is an example of x3270's peer script facility:

Code:

#!/usr/bin/perl

my @s3270 = s3270;

use IPC::Run qw( start pump finish timeout );
$IPCRUNDEBUG=details;
      # Incrementally read from / write to scalars.
      # $in is drained as it is fed to s3270's stdin,
      # $out accumulates s3270's stdout
      # $err accumulates s3270's stderr
      # $h is for "harness".
      my $h = start \@s3270, \$in, \$out, \$err, timeout( 10 );

      $in .= "connect(L:ssl3270.myhost.org:2023)\n";
      $in .= "ascii\n";

      $in .= "quit";
      finish $h or die "s3270 returned $?";

      warn $err if $err;
      print $out;         ## All of cat's output

hope this helps any googlers interested in scripting with s3270.

Chris, Thanks again