Synopsis:
exec [<shell commands>]
exec -direct <commands>
exec -name <name> <shell commands>
exec -out <process id|shell commands>
exec -msg <nickname|channel> <process id|shell commands>
exec -notice <nickname|channel> <process id|shell commands>
exec -in <process id> <text to send to process>
exec -window <process id|shell commands>
exec -<signal> <process id>
exec -close <process id>
Description:
EXEC allows you to spawn other processes from within your client,
which are naturally treated as child processes. For example, if you
wished to check your email without suspending your client (or
quitting irc), you could simply EXEC your favorite mail program.
Processes can be given unique names, allowing them to be referred to
more intuitively than trying to figure out its process id number.
Processes can also accept any signal normally available through use
of the Unix "kill" command (letting you kill, suspend, etc. any
process that accepts such a signal). Process identifiers begin with
a "%". Thus, a process named "mail" with pid 0 could be referred to
as either "%mail" or "%0".
EXEC can take several different flags, each of which allow you to
manipulate the subprocess in different ways. At the most basic
level, the only argument you really need to give is the external
program to run. If no arguments are given at all, a list of any
currently running processes is returned.
When using the -OUT, -MSG, or -NOTICE flags, output can be sent to
the target upon startup of the subprocess, or redirected to it after
it's already running by using its process id.
Another flag of note, -CLOSE, can be used to shut down renegade
subprocesses that simply won't go away (i.e. with their own quit
command, with the KILL signal, etc.). This actually just severs the
link between the subprocess and the client, so it will die on its
own the next time it tries to send data to the client.
Something to remember when worried about a shell processing arguments
is the -DIRECT flag, which executes the commands without spawning a
shell. This can cut down on security risks, and save some memory.
Options:
-direct executes commands without spawning a shell
-name give the subprocess a logical name
-out send subprocess output to your current channel
-msg send subprocess output to a nick or channel with MSG
-notice send subprocess output to a nick or channel with NOTICE
-in send a text string to the specified subprocess
-window redirect subprocess output to another window
-<signal> send SIG<signal> to the subprocess
-close forcibly kill the subprocess and its children
Examples:
(Assume that the process used with these examples is the Unix mail
program.)
To start a process:
/exec mail
To start a process without a shell interfering:
/exec -direct mail
To start a process and give it a human-readable name:
/exec -name mail mail
To send the output of a new subprocess to your current channel:
/exec -out mail
To send the output of a running subprocess to JoeBob with a MSG :
/exec -msg joebob %mail
To send the output of a new subprocess to #blah with a NOTICE :
/exec -notice #blah mail
To send a text string (command) to a running subprocess:
/exec -in %mail ?
To send a running subprocess the KILL signal:
/exec -kill %mail
To forcibly close down a stubborn subprocess that just won't die:
/exec -close %mail
Aliases:
When using EXEC with the -IN flag, the functionality is identical to
using MSG to send a message to a process. See MSG for more
information.
See Also:
msg (1); set (4) exec_protection , notify_on_termination , security , shell ,
shell_flags , shell_limit
Restrictions:
Use of external programs from within irc can sometimes be dangerous
if you don't know what you're doing. The danger doesn't necessarily
lie in the external programs themselves, but rather in any lack of
knowledge about them you may have. When all else fails, don't use a
command if you don't know what it does.
You can explicitly limit your ability to use EXEC in several ways.
If EXEC_PROTECTION is set to ON, ircII-EPIC will not permit EXEC to
be used from within any ON hook. If SECURITY has the 1 bit set, the
client will only permit EXEC to be used interactively; using it from
within aliases is not allowed. For real security, you can #define
RESTRICTED at compile time, which will completely disable EXEC .
Other Notes:
The available signals that may be sent to a process will vary from system
to system.
