1pulseaudio(1) General Commands Manual pulseaudio(1)
2
6 pulseaudio - The PulseAudio Sound System
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9 pulseaudio [options]
10 pulseaudio --help
12 pulseaudio --version
14 pulseaudio --dump-conf
16 pulseaudio --dump-modules
18 pulseaudio --dump-resample-methods
20 pulseaudio --cleanup-shm
22 pulseaudio --start
24 pulseaudio --kill
26 pulseaudio --check
28
30 PulseAudio is a networked low-latency sound server for Linux, POSIX and
31 Windows systems.
32
34 -h | --help
35 Show help.
36 --version
38 Show version information.
39 --dump-conf
41 Load the daemon configuration file daemon.conf (see below),
42 parse remaining configuration options on the command line and
43 dump the resulting daemon configuration, in a format that is
44 compatible with daemon.conf.
45 --dump-modules
47 List available loadable modules. Combine with -v for a more
48 elaborate listing.
49 --dump-resample-methods
51 List available audio resamplers.
52 --cleanup-shm
54 Identify stale PulseAudio POSIX shared memory segments in
55 /dev/shm and remove them if possible. This is done implicitly
56 whenever a new daemon starts up or a client tries to connect to
57 a daemon. It should normally not be necessary to issue this com‐
58 mand by hand. Only available on systems with POSIX shared memory
59 segments implemented via a virtual file system mounted to
60 /dev/shm (e.g. Linux).
61 --start
63 Start PulseAudio if it is not running yet. This is different
64 from starting PulseAudio without --start which would fail if PA
65 is already running. PulseAudio is guaranteed to be fully ini‐
66 tialized when this call returns. Implies --daemonize.
67 -k | --kill
69 Kill an already running PulseAudio daemon of the calling user
70 (Equivalent to sending a SIGTERM).
71 --check
73 Return 0 as return code when the PulseAudio daemon is already
74 running for the calling user, or non-zero otherwise. Produces no
75 output on the console except for errors to stderr.
76 Note that a non-zero return value doesn't necessarily mean that
78 PulseAudio is not usable. Even if the server is not running, it
79 may get automatically started via PulseAudio's autospawning
80 mechanism or systemd's socket activation, or the environment
81 might be such that checking for processes doesn't work (for
82 example, the running server might not show up in a container,
83 even if the server is accessible via a socket). Also disabling
84 PID files with --use-pid-file=no prevents --check from detecting
85 running servers.
86 A more robust check in most situations would be to try estab‐
88 lishing a client connection to the server. Unfortunately there's
89 currently no --check-connection option to replace --check, but
90 running "pactl info" could be a pretty good substitute.
91 --system[=BOOL]
93 Run as system-wide instance instead of per-user. Please note
94 that this disables certain features of PulseAudio and is gener‐
95 ally not recommended unless the system knows no local users
96 (e.g. is a thin client). This feature needs special configura‐
97 tion and a dedicated UNIX user set up. It is highly recommended
98 to combine this with --disallow-module-loading (see below).
99 -D | --daemonize[=BOOL]
101 Daemonize after startup, i.e. detach from the terminal. Note
102 that when running as a systemd service you should use --daemo‐
103 nize=no for systemd notification to work.
104 --fail[=BOOL]
106 Fail startup when any of the commands specified in the startup
107 script default.pa (see below) fails.
108 --high-priority[=BOOL]
110 Try to acquire a high Unix nice level. This will only succeed if
111 the calling user has a non-zero RLIMIT_NICE resource limit set
112 (on systems that support this), or we're configured to be run as
113 system daemon (see --system above). It is recommended to enable
114 this, since it is only a negligible security risk (see below).
115 --realtime[=BOOL]
117 Try to acquire a real-time scheduling for PulseAudio's I/O
118 threads. This will only succeed if the calling user has a non-
119 zero RLIMIT_RTPRIO resource limit set (on systems that support
120 this), or rtkit is available and allows PulseAudio to enable
121 real-time scheduling, or we are configured to be run as system
122 daemon (see --system above).
123 --disallow-module-loading[=BOOL]
125 Disallow module loading after startup. This is a security fea‐
126 ture since it disallows additional module loading during runtime
127 and on user request. It is highly recommended when --system is
128 used (see above). Note however, that this breaks certain fea‐
129 tures like automatic module loading on hot plug.
130 --disallow-exit[=BOOL]
132 Disallow user requested exit
133 --exit-idle-time=SECS
135 Terminate the daemon after the last client quit and this time in
136 seconds passed. Use a negative value to disable this feature.
137 Defaults to 20.
138 When PulseAudio runs in the per-user mode and detects a login
140 session, then any positive value will be reset to 0 so that
141 PulseAudio will terminate immediately on logout. A positive
142 value therefore has effect only in environments where there's no
143 support for login session tracking (or if the user is logged in
144 without a session spawned, a.k.a. lingering). A negative value
145 can still be used to disable any automatic exit.
146 When PulseAudio runs in the system mode, automatic exit is
148 always disabled, so this option does nothing.
149 --scache-idle-time=SECS
151 Unload autoloaded samples from the cache when they haven't been
152 used for the specified number of seconds.
153 --log-level[=LEVEL]
155 If an argument is passed, set the log level to the specified
156 value, otherwise increase the configured verbosity level by one.
157 The log levels are numerical from 0 to 4, corresponding to
158 error, warn, notice, info, debug. Default log level is notice,
159 i.e. all log messages with lower log levels are printed: error,
160 warn, notice.
161 -v | --verbose
163 Increase the configured verbosity level by one (see --log-level
164 above). Specify multiple times to increase log level multiple
165 times.
166 --log-target={auto,syslog,journal,stderr,file:PATH,newfile:PATH}
168 Specify the log target. If set to auto (which is the default),
169 then logging is directed to syslog when --daemonize is passed,
170 otherwise to STDERR. If set to journal logging is directed to
171 the systemd journal. If set to file:PATH, logging is directed to
172 the file indicated by PATH. newfile:PATH is otherwise the same
173 as file:PATH, but existing files are never overwritten. If the
174 specified file already exists, a suffix is added to the file
175 name to avoid overwriting.
176 --log-meta[=BOOL]
178 Show source code location in log messages.
179 --log-time[=BOOL]
181 Show timestamps in log messages.
182 --log-backtrace=FRAMES
184 When FRAMES is greater than 0, log for each message a stack
185 trace up to the number of specified stack frames.
186 -p | --dl-search-path=PATH
188 Set the search path for dynamic shared objects (plugins).
189 --resample-method=METHOD
191 Use the specified resampler by default (See --dump-resample-
192 methods above for possible values).
193 --use-pid-file[=BOOL]
195 Create a PID file. If this options is disabled it is possible to
196 run multiple sound servers per user.
197 --no-cpu-limit[=BOOL]
199 Do not install CPU load limiter on platforms that support it. By
200 default, PulseAudio will terminate itself when it notices that
201 it takes up too much CPU time. This is useful as a protection
202 against system lockups when real-time scheduling is used (see
203 below). Disabling this mechanism is useful when debugging
204 PulseAudio with tools like valgrind(1) which slow down execu‐
205 tion.
206 --disable-shm[=BOOL]
208 PulseAudio clients and the server can exchange audio data via
209 POSIX or memfd shared memory segments (on systems that support
210 this). If disabled PulseAudio will communicate exclusively over
211 sockets. Please note that data transfer via shared memory seg‐
212 ments is always disabled when PulseAudio is running with --sys‐
213 tem enabled (see above).
214 --enable-memfd[=BOOL]
216 PulseAudio clients and the server can exchange audio data via
217 memfds - the anonymous Linux Kernel shared memory mechanism (on
218 kernels that support this). If disabled PulseAudio will communi‐
219 cate via POSIX shared memory.
220 -L | --load="MODULE ARGUMENTS"
222 Load the specified plugin module with the specified arguments.
223 -F | --file=FILENAME
225 Run the specified script on startup. May be specified multiple
226 times to specify multiple scripts to be run in order. Combine
227 with -n to disable loading of the default script default.pa (see
228 below).
229 -C Open a command interpreter on STDIN/STDOUT after startup. This
231 may be used to configure PulseAudio dynamically during runtime.
232 Equivalent to --load=module-cli.
233 -n Don't load default script file default.pa (see below) on
235 startup. Useful in conjunction with -C or --file.
236
238 ~/.config/pulse/daemon.conf, /etc/pulse/daemon.conf: configuration set‐
239 tings for the PulseAudio daemon. If the version in the user's home
240 directory does not exist the global configuration file is loaded. See
241 pulse-daemon.conf(5) for more information.
242 ~/.config/pulse/default.pa, /etc/pulse/default.pa: the default configu‐
244 ration script to execute when the PulseAudio daemon is started. If the
245 version in the user's home directory does not exist the global configu‐
246 ration script is loaded. See default.pa(5) for more information.
247 ~/.config/pulse/client.conf, /etc/pulse/client.conf: configuration set‐
249 tings for PulseAudio client applications. If the version in the user's
250 home directory does not exist the global configuration file is loaded.
251 See pulse-client.conf(5) for more information.
252
254 SIGINT, SIGTERM: the PulseAudio daemon will shut down (Same as --kill).
255 SIGHUP: dump a long status report to STDOUT or syslog, depending on the
257 configuration.
258 SIGUSR1: load module-cli, allowing runtime reconfiguration via
260 STDIN/STDOUT.
261 SIGUSR2: load module-cli-protocol-unix, allowing runtime reconfigura‐
263 tion via a AF_UNIX socket. See pacmd(1) for more information.
264
266 Group pulse-access: if PulseAudio is running as a system daemon (see
267 --system above) access is granted to members of this group when they
268 connect via AF_UNIX sockets. If PulseAudio is running as a user daemon
269 this group has no meaning.
270 User pulse, group pulse: if PulseAudio is running as a system daemon
272 (see --system above) and is started as root the daemon will drop privi‐
273 leges and become a normal user process using this user and group. If
274 PulseAudio is running as a user daemon this user and group has no mean‐
275 ing.
276
278 To minimize the risk of drop-outs during playback it is recommended to
279 run PulseAudio with real-time scheduling if the underlying platform
280 supports it. This decouples the scheduling latency of the PulseAudio
281 daemon from the system load and is thus the best way to make sure that
282 PulseAudio always gets CPU time when it needs it to refill the hardware
283 playback buffers. Unfortunately this can be a security risk on some
284 systems, since PulseAudio runs as user process, and giving realtime
285 scheduling privileges to a user always comes with the risk that the
286 user misuses it to lock up the system -- which is possible since making
287 a process real-time effectively disables preemption. To solve this
288 problem, PulseAudio uses rtkit to safely acquire real-time scheduling
289 when available.
290 If the risk of locking up the machine is considered too big to enable
292 real-time scheduling, high-priority scheduling can be enabled instead
293 (i.e. negative nice level). This can be enabled by passing --high-pri‐
294 ority (see above) when starting PulseAudio and may also be enabled with
295 the appropriate option in daemon.conf. Negative nice levels can only be
296 enabled when the appropriate resource limit RLIMIT_NICE is set (see
297 setrlimit(2) for more information), possibly configured in /etc/secu‐
298 rity/limits.conf. A resource limit of 31 (corresponding with nice level
299 -11) is recommended.
300
302 The PulseAudio client libraries check for the existence of the follow‐
303 ing environment variables and change their local configuration accord‐
304 ingly:
305 $PULSE_SERVER: the server string specifying the server to connect to
307 when a client asks for a sound server connection and doesn't explicitly
308 ask for a specific server. The server string is a list of server
309 addresses separated by whitespace which are tried in turn. A server
310 address consists of an optional address type specifier (unix:, tcp:,
311 tcp4:, tcp6:), followed by a path or host address. A host address may
312 include an optional port number. A server address may be prefixed by a
313 string enclosed in {}. In this case the following server address is
314 ignored unless the prefix string equals the local hostname or the
315 machine id (/etc/machine-id).
316 $PULSE_SINK: the symbolic name of the sink to connect to when a client
318 creates a playback stream and doesn't explicitly ask for a specific
319 sink.
320 $PULSE_SOURCE: the symbolic name of the source to connect to when a
322 client creates a record stream and doesn't explicitly ask for a spe‐
323 cific source.
324 $PULSE_BINARY: path of PulseAudio executable to run when server auto-
326 spawning is used.
327 $PULSE_CLIENTCONFIG: path of file that shall be read instead of
329 client.conf (see above) for client configuration.
330 $PULSE_COOKIE: path of file that contains the PulseAudio authentication
332 cookie. Defaults to ~/.config/pulse/cookie.
333 These environment settings take precedence -- if set -- over the con‐
335 figuration settings from client.conf (see above).
336
338 The PulseAudio Developers <pulseaudio-discuss (at) lists (dot)
339 freedesktop (dot) org>; PulseAudio is available from http://pulseau‐
340 dio.org/
341
343 pulse-daemon.conf(5), default.pa(5), pulse-client.conf(5), pacmd(1)
344Manuals User pulseaudio(1)