NAME

alteratord - a daemon to interact with alterator backends.

SYNOPSIS

alteratord [ -ld ] [ -t <sec> ]

DESCRIPTION

alteratord process waits for incoming configuration requests and sends them to appropriate backends. Loaded backends are resident in memory for possible reuse. After 5 hours of inactivity a backend will be unloaded. Please note that unloading will not take place asynchronously but at nearest incoming request only. All backends will automatically receive SIGHUP signal when alteratord exits. You can trap this signal in a backend to perform some cleanup actions.

The process communicates using local domain socket. You should be superuser (root) or member of group _alteratord to have access to this socket.

Attention: Current implementation is NOT reenterable (doesn't support multiple requests at the same time), so you cannot call alteratord (other backends) inside backend code.

alteratord supports different execution schemas.
1. Start every time at system boot. Please note that alteratord service is turned off by default.
2. Start as a subprocess and exit when main process exits. This mode is used in acc, alterator-standalone, and in local mode of all interface frameworks (ahttpd, alterator-cmdline, and alterator-standalone).
3. Start on demand (using special helper) and exit automatically after 1 minute of inactivity. All interfaces will try to execute alteratord in this mode if it's is unavailable.

Please note that some backends can lock system resources, e.g. RPM package database.

OPTIONS

-l,--local

Local mode. This is a special mode for developers. alteratord will try to use backends and guile modules from local project directory. In this mode ALTERATOR_DEBUG environment variable is exported with value 1. Some libraries use this variable, e.g. alterator-sh-functions for write_debug().

-d,--debug

Turn on additional debug in Scheme interpreter. This is useful for debugging alteratord itself.

-t,--timeout <sec>

Exit automatically after specified number of seconds of inactivity.

ENVIRONMENT VARIABLES

alteratord and backends can use some environment variables. Multiple values are separated by a colon.

ALTERATOR_DATADIR

Directories with platfrom independent data. Some backends, e.g. help and menu can also use this variable.

Default value is /usr/share/alterator.

ALTERATOR_LIBDIR

Directories with scripts and binary programs (not libraries). There are various backends and hooks for communications between backends.

Default value is /usr/lib/alterator.

FILES

/usr/lib/alterator/interfaces/guile

Scheme libraries.

/usr/lib/alterator/backend3

Directory for backends.

/usr/lib/alteratord/control

Helper utility to run alteratord on demand. This program is SUID root and is available to members of _alteratord group only.

/run/alteratord/.socket

Local domain socket to communicate with alteratord.

/var/log/alteratord.log

Backends' stderr gets stored here. This file is recreated at every restart. If alteratord is staying in foreground this file is not used.

AUTHOR

Stanislav Ievlev <inger@altlinux.org>

SEE ALSO

ahttpd(8), alterator-cmdline(8)