# phpman > info > svscan

[svscan(8)](https://www.chedong.com/phpMan.php/man/svscan/8/markdown)                   System Manager's Manual                  [svscan(8)](https://www.chedong.com/phpMan.php/man/svscan/8/markdown)

NAME
       svscan - starts and monitors a collection of services

SYNOPSIS
       svscan [ directory ]

DESCRIPTION
       svscan  starts  one  [supervise(8)](https://www.chedong.com/phpMan.php/man/supervise/8/markdown)  process for each subdirectory of the
       current directory, up to a limit of 1000 subdirectories.  svscan  skips
       subdirectory  names  starting  with dots.  [supervise(8)](https://www.chedong.com/phpMan.php/man/supervise/8/markdown) must be in svs-
       can's path.

       svscan optionally starts a pair of [supervise(8)](https://www.chedong.com/phpMan.php/man/supervise/8/markdown) processes,  one  for  a
       subdirectory  s,  one for s/log, with a pipe between them. It does this
       if the name s is at most 255 bytes long and s/log exists. (In  versions
       0.70  and  below,  it does this if s is sticky.)  svscan needs two free
       descriptors for each pipe.

       Every five seconds, svscan checks for subdirectories again. If it  sees
       a new subdirectory, it starts a new [supervise(8)](https://www.chedong.com/phpMan.php/man/supervise/8/markdown) process. If it sees an
       old subdirectory where a [supervise(8)](https://www.chedong.com/phpMan.php/man/supervise/8/markdown) process has exited,  it  restarts
       the  [supervise(8)](https://www.chedong.com/phpMan.php/man/supervise/8/markdown)  process.  In the log case it reuses the same pipe so
       that no data is lost.

       svscan is designed to run forever. If it has trouble creating a pipe or
       running  [supervise(8)](https://www.chedong.com/phpMan.php/man/supervise/8/markdown), it prints a message to stderr; it will try again
       five seconds later.

       If svscan is given a command-line argument directory,  it  switches  to
       that directory when it starts.

SEE ALSO
       [supervise(8)](https://www.chedong.com/phpMan.php/man/supervise/8/markdown),  [svc(8)](https://www.chedong.com/phpMan.php/man/svc/8/markdown),  [svok(8)](https://www.chedong.com/phpMan.php/man/svok/8/markdown),  [svstat(8)](https://www.chedong.com/phpMan.php/man/svstat/8/markdown), [svscanboot(8)](https://www.chedong.com/phpMan.php/man/svscanboot/8/markdown), readprocti-
       [tle(8)](https://www.chedong.com/phpMan.php/man/tle/8/markdown), [fghack(8)](https://www.chedong.com/phpMan.php/man/fghack/8/markdown), [pgrphack(8)](https://www.chedong.com/phpMan.php/man/pgrphack/8/markdown), [multilog(8)](https://www.chedong.com/phpMan.php/man/multilog/8/markdown), [tai64n(8)](https://www.chedong.com/phpMan.php/man/tai64n/8/markdown), [tai64nlocal(8)](https://www.chedong.com/phpMan.php/man/tai64nlocal/8/markdown),
       [setuidgid(8)](https://www.chedong.com/phpMan.php/man/setuidgid/8/markdown), [envuidgid(8)](https://www.chedong.com/phpMan.php/man/envuidgid/8/markdown), [envdir(8)](https://www.chedong.com/phpMan.php/man/envdir/8/markdown), [softlimit(8)](https://www.chedong.com/phpMan.php/man/softlimit/8/markdown), [setlock(8)](https://www.chedong.com/phpMan.php/man/setlock/8/markdown)

       <http://cr.yp.to/daemontools.html>

                                                                     [svscan(8)](https://www.chedong.com/phpMan.php/man/svscan/8/markdown)