Document: Scripts

Scripts

This documents describes how to use scripts to
automate tasks within eboard.

Felipe Bergo 

1. Language and Location
2. Requirements and I/O
3. FICS auto login

---

1. Language and Location

Scripts must be placed in ~/.eboard/scripts, must be
owned by the user and must be readable and executable
by him (mode u+rx).

To run a generic script, select Windows -> Run Script,
all scripts found will be listed.

Scripts can be in any scripting language you prefer.
I recommend expect for the very simple scripts and
Perl for the trickier ones.

2. Requirements and I/O

After the script is running, every line of text received
from the peer (either ICS server or chess engine) is
sent to the scripts STDIN (standard input).

The script must not buffer its output, else eboard will
lock up.

*The script must write a line to STDOUT (terminated by \n)
as soon as it starts* -- this is used to detect that the
script is running and this first line is discarded (not
sent to the eboard peer).

Any further output written to the script's STDOUT will
be sent to the peer (ICS server / chess engine).

The Script List window is capable of retrieving a
description line for the script. Such a description
is recognized if
 
 (a) the  first character of the file is '#'

 (b) there is a comment line started by '#' from
     the file's second line on.

The first requirement if meant to avoid reading data from
files that do not start with '#!/usr/bin/perl' (in the future
other languages may be supported).


3. FICS auto login

Whenever a connection to FICS is accomplished with the
Peer -> Connect to FICS command, eboard will try to
run a script named 'autofics.pl'.
If you want to perform an automatic login, write an
autofics.pl that provides your handle and password.

*Notice*: the .pl extension is reminiscent from previous
eboard versions where all scripts must be written in
Perl. You can write autofics.pl in whatever language you
desire, but the file name must still be autofics.pl.

*Notice*: this can be quite a security flaw, because
the password will be stored in cleartext in the script.
I take no responsibility for it. If someone else
have access to your password and abuses your FICS account
(someone else connecting with your login is already abuse),
it is your fault and your responsibility. Be sure to
chmod 700 the autofics.pl file if you use this facility.

Here are two sample login scripts for user 'foo' with password
'bar', first in expect, next in Perl.
Notice the description comment and the initialization
to prevent STDOUT buffering.

--------8<-----------------8<----------------
#!/usr/bin/expect -f

# my fics auto login script in expect

send "hello\n"
expect ogin:
send "foo\n"
expect word:
send "bar\n"
--------8<-----------------8<----------------


--------8<-----------------8<----------------
#!/usr/bin/perl

# my fics auto login script in perl

# set autoflush on stdout
select(STDOUT); $| = 1;

# proof of life to avoid hanging
print "hello\n";

# while there is input in STDIN, read a line
while(<>) {
	  print "foo\n" if /login:/;
	  if (/password:/) {
	     print "bar\n";
	     exit 0;
	  }
}
--------8<-----------------8<----------------

Please don't bug me with questions about the
Perl language -- for help with it see the
'man perl' man page, especially
'man perlipc' about I/O flushing and
'man perlre' about regular expressions
(the patterns /login:/ and /password:/ above
are a very simple example),
and 'man perlfunc' for a list of built-in
functions.