Provided by: pulseaudio_16.1+dfsg1-2ubuntu4.1_amd64 bug

NAME

       pulseaudio - The PulseAudio Sound System

SYNOPSIS

       pulseaudio [options]

       pulseaudio --help

       pulseaudio --version

       pulseaudio --dump-conf

       pulseaudio --dump-modules

       pulseaudio --dump-resample-methods

       pulseaudio --cleanup-shm

       pulseaudio --start

       pulseaudio --kill

       pulseaudio --check

DESCRIPTION

       PulseAudio is a networked low-latency sound server for Linux, POSIX and Windows systems.

OPTIONS

       -h | --help
              Show help.

       --version
              Show version information.

       --dump-conf
              Load  the  daemon  configuration  file  daemon.conf  (see  below),  parse remaining
              configuration  options  on  the  command  line  and  dump  the   resulting   daemon
              configuration, in a format that is compatible with daemon.conf.

       --dump-modules
              List available loadable modules. Combine with -v for a more elaborate listing.

       --dump-resample-methods
              List available audio resamplers.

       --cleanup-shm
              Identify  stale PulseAudio POSIX shared memory segments in /dev/shm and remove them
              if possible. This is done implicitly whenever a new daemon starts up  or  a  client
              tries  to  connect  to  a daemon. It should normally not be necessary to issue this
              command by hand. Only available  on  systems  with  POSIX  shared  memory  segments
              implemented via a virtual file system mounted to /dev/shm (e.g. Linux).

       --start
              Start  PulseAudio  if  it  is  not  running  yet.  This  is different from starting
              PulseAudio without --start which would fail if PA is already running. PulseAudio is
              guaranteed to be fully initialized when this call returns. Implies --daemonize.

       -k | --kill
              Kill  an  already  running  PulseAudio  daemon  of  the calling user (Equivalent to
              sending a SIGTERM).

       --check
              Return 0 as return code when the PulseAudio  daemon  is  already  running  for  the
              calling  user,  or non-zero otherwise. Produces no output on the console except for
              errors to stderr.

              Note that a non-zero return value doesn't necessarily mean that PulseAudio  is  not
              usable.  Even  if  the  server is not running, it may get automatically started via
              PulseAudio's  autospawning  mechanism  or  systemd's  socket  activation,  or   the
              environment  might  be  such that checking for processes doesn't work (for example,
              the running server might not show  up  in  a  container,  even  if  the  server  is
              accessible  via a socket). Also disabling PID files with --use-pid-file=no prevents
              --check from detecting running servers.

              A more robust check in most situations  would  be  to  try  establishing  a  client
              connection  to  the  server.  Unfortunately there's currently no --check-connection
              option to replace --check,  but  running  "pactl  info"  could  be  a  pretty  good
              substitute.

       --system[=BOOL]
              Run  as  system-wide  instance  instead of per-user. Please note that this disables
              certain features of PulseAudio and is generally not recommended unless  the  system
              knows  no  local  users  (e.g.  is  a  thin  client).  This  feature  needs special
              configuration and a dedicated UNIX user set up. It is highly recommended to combine
              this with --disallow-module-loading (see below).

       -D | --daemonize[=BOOL]
              Daemonize after startup, i.e. detach from the terminal. Note that when running as a
              systemd service you should use --daemonize=no for systemd notification to work.

       --fail[=BOOL]
              Fail startup when any of the commands specified in the  startup  script  default.pa
              (see below) fails.

       --high-priority[=BOOL]
              Try  to  acquire a high Unix nice level. This will only succeed if the calling user
              has a non-zero RLIMIT_NICE resource limit set (on systems that  support  this),  or
              we're configured to be run as system daemon (see --system above). It is recommended
              to enable this, since it is only a negligible security risk (see below).

       --realtime[=BOOL]
              Try to acquire a real-time scheduling for PulseAudio's I/O threads. This will  only
              succeed  if  the  calling  user has a non-zero RLIMIT_RTPRIO resource limit set (on
              systems that support this), or rtkit is available and allows PulseAudio  to  enable
              real-time scheduling, or we are configured to be run as system daemon (see --system
              above).

       --disallow-module-loading[=BOOL]
              Disallow module loading  after  startup.  This  is  a  security  feature  since  it
              disallows  additional  module  loading  during  runtime  and on user request. It is
              highly recommended when --system is used  (see  above).  Note  however,  that  this
              breaks certain features like automatic module loading on hot plug.

       --disallow-exit[=BOOL]
              Disallow user requested exit

       --exit-idle-time=SECS
              Terminate  the  daemon  after the last client quit and this time in seconds passed.
              Use a negative value to disable this feature. Defaults to 20.

              When PulseAudio runs in the per-user mode and detects a  login  session,  then  any
              positive  value will be reset to 0 so that PulseAudio will terminate immediately on
              logout. A positive value therefore has effect only in environments where there's no
              support  for  login session tracking (or if the user is logged in without a session
              spawned, a.k.a. lingering). A negative value can  still  be  used  to  disable  any
              automatic exit.

              When PulseAudio runs in the system mode, automatic exit is always disabled, so this
              option does nothing.

       --scache-idle-time=SECS
              Unload autoloaded samples from the cache  when  they  haven't  been  used  for  the
              specified number of seconds.

       --log-level[=LEVEL]
              If  an  argument  is  passed,  set  the log level to the specified value, otherwise
              increase the configured verbosity level by one. The log levels are numerical from 0
              to  4,  corresponding  to  error,  warn,  notice, info, debug. Default log level is
              notice, i.e. all log messages with lower  log  levels  are  printed:  error,  warn,
              notice.

       -v | --verbose
              Increase  the  configured  verbosity  level by one (see --log-level above). Specify
              multiple times to increase log level multiple times.

       --log-target={auto,syslog,journal,stderr,file:PATH,newfile:PATH}
              Specify the log target. If set to auto (which is  the  default),  then  logging  is
              directed  to  syslog  when  --daemonize  is  passed, otherwise to STDERR. If set to
              journal logging is directed to the systemd journal. If set to file:PATH, logging is
              directed  to  the  file  indicated  by  PATH. newfile:PATH is otherwise the same as
              file:PATH, but existing files are never overwritten. If the specified file  already
              exists, a suffix is added to the file name to avoid overwriting.

       --log-meta[=BOOL]
              Show source code location in log messages.

       --log-time[=BOOL]
              Show timestamps in log messages.

       --log-backtrace=FRAMES
              When  FRAMES is greater than 0, log for each message a stack trace up to the number
              of specified stack frames.

       -p | --dl-search-path=PATH
              Set the search path for dynamic shared objects (plugins).

       --resample-method=METHOD
              Use the specified resampler  by  default  (See  --dump-resample-methods  above  for
              possible values).

       --use-pid-file[=BOOL]
              Create a PID file. If this options is disabled it is possible to run multiple sound
              servers per user.

       --no-cpu-limit[=BOOL]
              Do not install  CPU  load  limiter  on  platforms  that  support  it.  By  default,
              PulseAudio  will  terminate  itself  when  it notices that it takes up too much CPU
              time. This is  useful  as  a  protection  against  system  lockups  when  real-time
              scheduling  is  used (see below). Disabling this mechanism is useful when debugging
              PulseAudio with tools like valgrind(1) which slow down execution.

       --disable-shm[=BOOL]
              PulseAudio clients and the server can exchange audio data via POSIX or memfd shared
              memory  segments  (on  systems  that  support  this).  If  disabled PulseAudio will
              communicate exclusively over sockets. Please note that  data  transfer  via  shared
              memory segments is always disabled when PulseAudio is running with --system enabled
              (see above).

       --enable-memfd[=BOOL]
              PulseAudio clients and the  server  can  exchange  audio  data  via  memfds  -  the
              anonymous  Linux  Kernel shared memory mechanism (on kernels that support this). If
              disabled PulseAudio will communicate via POSIX shared memory.

       -L | --load="MODULE ARGUMENTS"
              Load the specified plugin module with the specified arguments.

       -F | --file=FILENAME
              Run the specified script on startup. May be specified  multiple  times  to  specify
              multiple  scripts  to  be  run  in order. Combine with -n to disable loading of the
              default script default.pa (see below).

       -C     Open a command interpreter on STDIN/STDOUT after  startup.  This  may  be  used  to
              configure PulseAudio dynamically during runtime. Equivalent to --load=module-cli.

       -n     Don't  load  default  script  file  default.pa  (see  below)  on startup. Useful in
              conjunction with -C or --file.

FILES

       ~/.config/pulse/daemon.conf,  /etc/pulse/daemon.conf:  configuration  settings   for   the
       PulseAudio  daemon.  If the version in the user's home directory does not exist the global
       configuration file is loaded. See pulse-daemon.conf(5) for more information.

       ~/.config/pulse/default.pa, /etc/pulse/default.pa: the  default  configuration  script  to
       execute when the PulseAudio daemon is started. If the version in the user's home directory
       does not exist the global configuration script  is  loaded.  See  default.pa(5)  for  more
       information.

       ~/.config/pulse/client.conf, /etc/pulse/client.conf: configuration settings for PulseAudio
       client applications. If the version in the user's home directory does not exist the global
       configuration file is loaded. See pulse-client.conf(5) for more information.

SIGNALS

       SIGINT, SIGTERM: the PulseAudio daemon will shut down (Same as --kill).

       SIGHUP: dump a long status report to STDOUT or syslog, depending on the configuration.

       SIGUSR1: load module-cli, allowing runtime reconfiguration via STDIN/STDOUT.

       SIGUSR2:  load  module-cli-protocol-unix,  allowing  runtime reconfiguration via a AF_UNIX
       socket. See pacmd(1) for more information.

UNIX GROUPS AND USERS

       Group pulse-access: if PulseAudio is running as  a  system  daemon  (see  --system  above)
       access  is  granted  to  members  of  this group when they connect via AF_UNIX sockets. If
       PulseAudio is running as a user daemon this group has no meaning.

       User pulse, group pulse: if PulseAudio is running as a system daemon (see --system  above)
       and  is  started  as root the daemon will drop privileges and become a normal user process
       using this user and group. If PulseAudio is running as a user daemon this user  and  group
       has no meaning.

REAL-TIME AND HIGH-PRIORITY SCHEDULING

       To minimize the risk of drop-outs during playback it is recommended to run PulseAudio with
       real-time scheduling if the underlying platform supports it. This decouples the scheduling
       latency  of  the  PulseAudio  daemon from the system load and is thus the best way to make
       sure that PulseAudio always gets CPU time when it needs it to refill the hardware playback
       buffers.  Unfortunately this can be a security risk on some systems, since PulseAudio runs
       as user process, and giving realtime scheduling privileges to a user always comes with the
       risk  that  the  user misuses it to lock up the system -- which is possible since making a
       process real-time effectively disables preemption. To solve this problem, PulseAudio  uses
       rtkit to safely acquire real-time scheduling when available.

       If  the  risk  of  locking  up  the  machine  is  considered  too  big to enable real-time
       scheduling, high-priority scheduling can be enabled instead (i.e.  negative  nice  level).
       This  can  be  enabled by passing --high-priority (see above) when starting PulseAudio and
       may also be enabled with the appropriate option in daemon.conf. Negative nice  levels  can
       only  be  enabled when the appropriate resource limit RLIMIT_NICE is set (see setrlimit(2)
       for more information), possibly configured in /etc/security/limits.conf. A resource  limit
       of 31 (corresponding with nice level -11) is recommended.

ENVIRONMENT VARIABLES

       The  PulseAudio  client  libraries  check  for  the existence of the following environment
       variables and change their local configuration accordingly:

       $PULSE_SERVER: the server string specifying the server to connect to when  a  client  asks
       for a sound server connection and doesn't explicitly ask for a specific server. The server
       string is a list of server addresses separated by whitespace which are tried  in  turn.  A
       server address consists of an optional address type specifier (unix:, tcp:, tcp4:, tcp6:),
       followed by a path or host address. A host address may include an optional port number.  A
       server  address  may  be  prefixed  by a string enclosed in {}. In this case the following
       server address is ignored unless the prefix  string  equals  the  local  hostname  or  the
       machine id (/etc/machine-id).

       $PULSE_SINK:  the symbolic name of the sink to connect to when a client creates a playback
       stream and doesn't explicitly ask for a specific sink.

       $PULSE_SOURCE: the symbolic name of the source to connect  to  when  a  client  creates  a
       record stream and doesn't explicitly ask for a specific source.

       $PULSE_BINARY: path of PulseAudio executable to run when server auto-spawning is used.

       $PULSE_CLIENTCONFIG:  path  of  file that shall be read instead of client.conf (see above)
       for client configuration.

       $PULSE_COOKIE: path of file that contains the PulseAudio authentication  cookie.  Defaults
       to ~/.config/pulse/cookie.

       These  environment  settings  take precedence -- if set -- over the configuration settings
       from client.conf (see above).

AUTHORS

       The PulseAudio Developers <pulseaudio-discuss (at) lists  (dot)  freedesktop  (dot)  org>;
       PulseAudio is available from http://pulseaudio.org/

SEE ALSO

       pulse-daemon.conf(5), default.pa(5), pulse-client.conf(5), pacmd(1)