LAUNCHTOOL(1)						      General Commands Manual						     LAUNCHTOOL(1)

NAME

       launchtool - run a command supervising its execution.

SYNOPSIS

       launchtool [options] [command]

DESCRIPTION

       launchtool  is  a tool that runs a user-supplied command and can supervise its execution in many ways, such as controlling its environment,
       blocking signals, logging its output, changing user and group permissions, limiting resource usage, restarting it if it fails,  running	it
       continuously and turning it into a daemon.

       launchtool  is  fully configurable, both through the commandline and using configuration files.	Configuration files can be made executable
       and start with "#!/usr/bin/launchtool -C", to create daemons using simpler commands.

INVOCATION

       launchtool executes the command it finds in the commandline, via switches or the configuration file.  All non-switch  parameters  are  con-
       catenated to the command, that will be executed using "/bin/sh -c".

       launchtool  default  mode  of execution is to run the command normally and return its exit status. All features are disabled by default and
       activated using commandline options or values in the configuration file.  Commandline options override configuration files.

       launchtool sessions are identified by a tag that is used both to mark the command output in logfiles and to identify  running  sessions	to
       check if they have already been started or send them a signal without specifying the process PID.

OPTIONS

       launchtool follows the usual GNU command line syntax, with long options starting with two dashes (`-').

       -?, --help
	      Display a detailed help message with a summary of all options.

       --usage
	      Display a brief usage message.

       -k, --kill[=signal]
	      Kill a running launchtool with the specified signal (15 by default) and exit.  No signal name parsing is (yet) provided, so the sig-
	      nal must be specified by its number.

       --check
	      Check if another launchtool is running, then exit.

       --showcfg
	      Process config files and commandline, show the resulting configuration and exit.

       -V, --version
	      Print version and exit.

       -t, --tag=tag, "tag"
	      Tag used to identify the session

       -C, --config=file
	      Read configuration data from "file".  Defaults to /etc/launchtool/<tag>.conf

       -v, --verbose, "verbose"
	      Enable verbose output.

       --no-verbose
	      Disable verbose output.

       --debug, "debug"
	      Enable debug output (includes --verbose output).

       --no-debug
	      Disable debug output.

       -c, --command=cmd, "command"
	      Command to execute.

       --visible-tag=tag, "visible tag"
	      Tag to use for pidfiles and logfiles instead of "launchtool-<tag>".

       -d, --daemon, "daemon"
	      Fork to background and detach from terminal, becoming a daemon.

       -n, --no-daemon
	      Don't become a daemon.

       --pidfile, "pidfile"
	      Create a pidfile (default when --daemon is used).

       --no-pidfile
	      Don't create a pidfile (default when --daemon is not used).

       --piddir=dir, "piddir"
	      Directory where pidfiles are stored (default to /var/run).

       --chroot=dir, "root dir"
	      Chroot to this directory before running the command.

       --chdir=dir, "start dir"
	      Chdir to this directory before running the command (default to '.' or '/' if --daemon is present).

       -u, --user=user, "user"
	      User privileges to run the command with.

       -g, --group=group, "group"
	      Group privileges to run the command with.

       --umask=mask, "umask"
	      Set this umask before running the command.

       -L, --infinite-runs, "infinite runs"
	      Never give up restarting the command if it fails.

       --no-infinite-runs
	      Give up restarting the command after a certain number of failures.

       --wait-times=t1,t2,... , "wait times"
	      List of times (in seconds) to wait after a program failure before restarting it.	If not specified,  failed  commands  will  not	be
	      restarted.

       --good-running-time=seconds, "good running time"
	      Minimum running time needed to restart for the first wait time.

       --forwarded-signals=sig1,sig2,... , "forwarded signals"
	      List of signals (in name or in number) to be forwarded to the command.

       --blocked-signals=sig1,sig2,... , "blocked signals"
	      List of signals (in name or in number) to be blocked before running the command.

       --limit-cpu=seconds, "cpu limit"
	      CPU time limit for the command (see setrlimit(2)).

       --limit-file-size=1024b-blocks, "file size limit"
	      File size limit for the command (see setrlimit(2)).

       --limit-data-memory=1024b-blocks, "data memory limit"
	      Data memory size limit for the command (see setrlimit(2)).

       --limit-process-count=count, "process count limit"
	      Process count limit for the command (see setrlimit(2)).

       --limit-open-files=count, "open files limit"
	      Open files limit for the command (see setrlimit(2)).

       --limit-core-size=1024b-blocks, "core size limit"
	      Core file size limit for the command (see setrlimit(2)).

       --restrict-environment, "restrict environment"
	      Restrict the child environment.

       --no-restrict-environment
	      Copy all environment variables to the child environment.

       --allowed-env-vars=var1,var2,... , "allowed env vars"
	      List of environment variables to be copied to the child when the environment is restricted.

       --log-launchtool-output=target, "launchtool output"
	      Target of the launchtool output (ignore, stdout, stderr, file:filename or syslog:identity,facility,level).

       --log-launchtool-errors=target, "launchtool errors"
	      Target of the launchtool error messages (ignore, stdout, stderr, file:filename or syslog:identity,facility,level).

       --log-child-output=target, "command output"
	      Target of the child output (ignore, stdout, stderr, file:filename or syslog:identity,facility,level).

       --log-child-errors=target, "command errors"
	      Target of the child error messages (ignore, stdout, stderr, file:filename or syslog:identity,facility,level).

       --silent-restart-status=value, "silent restart status"
	      Return value used by the child to explicitly request a restart (feature disabled if not specified).

       --silent-restart-time=seconds, "silent restart time"
	      Time to wait before restarting the child after an explicit restart request.

       --stats, "stats"
	      Produce some statistics when the command terminates (implied by --verbose).

       --no-stats
	      Do not produce statistics when the command terminates.

LOGGING TARGETS

       Logging targets are specified with a target name and its optional parameters, separated by a colon (":").

       Possible target configurations are:

       ignore Output is just discarded.

       stdout Output goes to the standard output stream.

       stderr Output goes to the standard error stream.

       file:filename
	      Output goes to the file "filename".

       syslog:identity,facility,level
	      Output  goes  to	syslog,  with  the  given identity (a string identifying the logger), facility (see syslog(3)) and level (see sys-
	      log(3)).

CONFIGURATION FILE

       The configuration file is a sequence of "key = value" lines.  Empty lines and lines starting with '#' are ignored.

       The possible keys have been listed in the OPTIONS section next to the corresponding commandline switch.

       Boolean (yes/no) values can take the values "yes", "no", "true", "false", "0" and "1".

EXAMPLES

       # Running a command normally

       launchtool -t tag 'echo "Hello, world!"'

       # Run a command restarting it if it fails:

       launchtool -t tag --wait-times=1,1,1,3,3,3,10,10,10 'my_wonderful_server'

       # Run a command, with restrictions, restarting it if it fails, as a daemon

       launchtool -t myserver -d --user=myserver    --chroot=/var/myserver 
	    --limit-process-count=5 --limit-open-files=10 
	    --wait-times=1,1,1,3,3,3,10,10,10 
	    --infinite-runs --stats 
	    --log-launchtool-output=syslog:myserver,LOG_DAEMON,LOG_INFO 
	    --log-launchtool-errors=syslog:myserver,LOG_DAEMON,LOG_ERR 
	    --log-child-output=syslog:myserver,LOG_DAEMON,LOG_INFO 
	    --log-child-errors=syslog:myserver,LOG_DAEMON,LOG_ERR 
	    'my_experimental_server'

       # Same thing, using a configuration file

       tag = myserver
       command = my_wonderful_server
       daemon = yes
       stats = yes
       user = myserver
       root dir = /var/myserver
       process count limit = 5
       open files limit = 10
       wait times = 1,1,1,3,3,3,10,10,10
       infinite runs = yes
       launchtool output = syslog:myserver,LOG_DAEMON,LOG_INFO
       launchtool errors = syslog:myserver,LOG_DAEMON,LOG_ERR
       command output = syslog:myserver,LOG_DAEMON,LOG_INFO
       command errors = syslog:myserver,LOG_DAEMON,LOG_ERR

       # Transform a shell command in a polling daemon
       # Make the file /tmp/have_mobile exist only if my cell phone is present in the
       # IRDA discovery list

       launchtool -t celldetect -d --silent-restart-time=5 --silent-restart-status=0 --user=nobody 
	    "if grep -q SIEMENS /proc/sys/net/irda/discovery; then touch /tmp/have_mobile; else rm -f /tmp/have_mobile; fi ; exit 0"

       # Ceck if the celldetect daemon is running

       launchtool -t celldetect --check

       # Kill the celldetect daemon launched with the command above

       launchtool -t celldetect -k

       # Same polling daemon, with an executable configuration file

       #!/usr/bin/launchtool -C
       tag = celldetect
       command = if grep -q SIEMENS /proc/sys/net/irda/discovery; then touch /tmp/have_mobile; else rm -f /tmp/have_mobile; fi ; exit 0
       daemon = yes
       user = nobody
       silent restart time = 5
       silent restart status = 0

       # Ceck if the celldetect daemon is running, using the executable configuration
       # file

       celldetect --check

       # Kill the celldetect daemon using the executable configuration file

       celldetect -k

SEE ALSO

       syslog(3), setrlimit(2).

AUTHOR

       launchtool has been written by Enrico Zini <enrico@debian.org>.

								 october 03, 2002						     LAUNCHTOOL(1)