X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsd_notify.xml;h=6bf823076332871f64bbf94c9b99b278f94a76cd;hp=346ec8f90b42d04a306eab914788885a296a3ea0;hb=05a2f6fefedd7254fd799502191d025d2908cf74;hpb=0675cc4a02dfa3e7abc47d0c2117bf413b1d7698 diff --git a/man/sd_notify.xml b/man/sd_notify.xml index 346ec8f90..6bf823076 100644 --- a/man/sd_notify.xml +++ b/man/sd_notify.xml @@ -21,7 +21,8 @@ along with systemd; If not, see . --> - + sd_notify @@ -77,9 +78,9 @@ notification. If the unset_environment - parameter is non-zero sd_notify() + parameter is non-zero, sd_notify() will unset the $NOTIFY_SOCKET - environment variable before returning (regardless + environment variable before returning (regardless of whether the function call itself succeeded or not). Further calls to sd_notify() will then fail, but @@ -87,7 +88,7 @@ processes. The state parameter - should contain an newline-separated list of variable + should contain a newline-separated list of variable assignments, similar in style to an environment block. A trailing newline is implied if none is specified. The string may contain any kind of variable @@ -104,7 +105,7 @@ definition file has Type=notify set. The passed argument is a boolean "1" or "0". Since there is little - value in signalling non-readiness, the + value in signaling non-readiness, the only value daemons should send is "READY=1". @@ -164,11 +165,15 @@ systemd.service5 for details. It is recommended to send this message if the - WATCHDOG_USEC= - environment variable has been set for - the service process, in every half the - time interval that is specified in the - variable. + $WATCHDOG_PID + environment variable has been set to + the PID of the service process, in + every half the time interval that is + specified in the + $WATCHDOG_USEC + environment variable. See + sd_watchdog_enabled3 + for details. @@ -197,64 +202,33 @@ errno-style error code. If $NOTIFY_SOCKET was not set and hence no status data could be sent, 0 is returned. If - the status was sent these functions return with a + the status was sent, these functions return with a positive return value. In order to support both, init systems that implement this scheme and those which - don't, it is generally recommended to ignore the return + do not, it is generally recommended to ignore the return value of this call. Notes - These functions are provided by the reference - implementation of APIs for new-style daemons and - distributed with the systemd package. The algorithms - they implement are simple, and can easily be - reimplemented in daemons if it is important to support - this interface without using the reference - implementation. + Internally, these functions send a single datagram with the state string as payload to the - AF_UNIX socket referenced in the + AF_UNIX socket referenced in the $NOTIFY_SOCKET environment variable. If the first character of - $NOTIFY_SOCKET is @ the string is + $NOTIFY_SOCKET is @, the string is understood as Linux abstract namespace socket. The datagram is accompanied by the process credentials of the sending daemon, using SCM_CREDENTIALS. - - For details about the algorithms check the - liberally licensed reference implementation sources: - - resp. - - sd_notify() and - sd_notifyf() are implemented in - the reference implementation's - sd-daemon.c and - sd-daemon.h files. These - interfaces are available as shared library, which can - be compiled and linked to with the - libsystemd-daemon - pkg-config1 - file. Alternatively, applications consuming these APIs - may copy the implementation into their source tree. For - more details about the reference implementation see - sd-daemon3. - - If the reference implementation is used as - drop-in files and -DDISABLE_SYSTEMD is set during - compilation these functions will always return 0 and - otherwise become a NOP. Environment - + $NOTIFY_SOCKET @@ -312,7 +286,8 @@ systemd1, sd-daemon3, daemon7, - systemd.service5 + systemd.service5, + sd_watchdog_enabled3