LOCK()

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Attempt to obtain a named mutex.

Last reviewed 2026-08-22

LOCK(lockname)
Description

Attempts to grab a named lock exclusively, and prevents other channels from obtaining the same lock. LOCK will wait for the lock to become available. Returns 1 if the lock was obtained or 0 on error.

Note

To avoid the possibility of a deadlock, LOCK will only attempt to obtain the lock for 3 seconds if the channelA single call leg passing through Asterisk. Channels represent connections to endpoints and are what dialplan applications act on. already has another lock.

Note

If live_dangerously in asterisk.conf is set to no, this function can only be executed from the dialplanThe core call-routing configuration of Asterisk, written mostly in extensions.conf as contexts, extensions, and priorities that decide how every call is handled. Full definition →, and not directly from external protocols.

Arguments
  • lockname required
User Notes

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Related

UUID()

Generates an UUID.

Functions function dialplan
STIR_SHAKEN_ATTESTATION()

Sets STIR/SHAKEN Attestation parameters on an outgoing channel.

Functions function dialplan
SET()

SET assigns a value to a channel variable.

Functions function dialplan
RECORDING_INFO()

Retrieve information about a recording previously created using the Record application

Functions function dialplan
PJSIP_TRANSFER_HANDLING()

Set how transfers are handled for a PJSIP channel.

Functions function dialplan
Functions
ABS() AES_DECRYPT() AES_ENCRYPT() AGC() AGENT() AMI_CLIENT() ARRAY() AST_CONFIG() AST_SORCERY() BASE64_DECODE() BASE64_ENCODE() BASENAME() BLACKLIST() CALENDAR_BUSY() CALENDAR_EVENT() CALENDAR_QUERY() CALENDAR_QUERY_RESULT() CALENDAR_WRITE() CALLCOMPLETION() CALLERID() CALLERPRES() CDR() CDR_PROP() CHANNEL() CHANNELS() CHANNEL_EXISTS() CHECKSIPDOMAIN() CONFBRIDGE() CONFBRIDGE_CHANNELS() CONFBRIDGE_INFO() CONNECTEDLINE() CSV_QUOTE() CURL() CURLOPT() CUT() DAHDI_CHANNEL() DB() DB_DELETE() DB_EXISTS() DB_KEYCOUNT() DB_KEYS() DEC() DELETE() DENOISE() DEVICE_STATE() DIALGROUP() DIALPLAN_EXISTS() DIGIT_SUM() DIRNAME() DUNDILOOKUP() DUNDIQUERY() DUNDIRESULT() ENUMLOOKUP() ENUMQUERY() ENUMRESULT() ENV() EVAL() EVAL_EXTEN() EVAL_SUB() EXCEPTION() EXISTS() EXPORT() EXTENSION_STATE() FAXOPT() FEATURE() FEATUREMAP() FIELDNUM() FIELDQTY() FILE() FILE_COUNT_LINE() FILE_FORMAT() FILTER() FRAME_DROP() FRAME_TRACE() GEOLOC_PROFILE() GLOBAL() GLOBAL_DELETE() GLOBAL_EXISTS() GROUP() GROUP_COUNT() GROUP_LIST() GROUP_MATCH_COUNT() HANGUPCAUSE() HANGUPCAUSE_KEYS() HASH() HASHKEYS() HINT() HOLD_INTERCEPT() IAXPEER() IAXVAR() ICONV() IF() IFMODULE() IFTIME() IMPORT() INC() ISNULL() JABBER_RECEIVE() JABBER_STATUS() JITTERBUFFER() JSON_DECODE() KEYPADHASH() LEN() LISTFILTER() LOCAL() LOCAL_PEEK() LOCK() LOG_GROUP() LTRIM() MAILBOX_EXISTS() MASTER_CHANNEL() MATH() MAX() MD5() MEETME_INFO() MESSAGE() MESSAGE_DATA() MIN() MINIVMACCOUNT() MINIVMCOUNTER() MIXMONITOR() MUTEAUDIO() ODBC() ODBC_FETCH() PARK_GET_CHANNEL() PASSTHRU() PERIODIC_HOOK() PITCH_SHIFT() PJSIP_AOR() PJSIP_CONTACT() PJSIP_DIAL_CONTACTS() PJSIP_DTMF_MODE() PJSIP_ENDPOINT() PJSIP_HEADER() PJSIP_HEADERS() PJSIP_HEADER_PARAM() PJSIP_INHERITABLE_HEADER() PJSIP_MEDIA_OFFER() PJSIP_MOH_PASSTHROUGH() PJSIP_PARSE_URI() PJSIP_PARSE_URI_FROM() PJSIP_RESPONSE_HEADER() PJSIP_RESPONSE_HEADERS() PJSIP_SEND_SESSION_REFRESH() PJSIP_TRANSFER_HANDLING() POLARITY() POP() PP_EACH_EXTENSION() PP_EACH_USER() PRESENCE_STATE() PUSH() QUEUE_EXISTS() QUEUE_GET_CHANNEL() QUEUE_MEMBER() QUEUE_MEMBER_COUNT() QUEUE_MEMBER_LIST() QUEUE_MEMBER_PENALTY() QUEUE_VARIABLES() QUEUE_WAITING_COUNT() QUOTE() RAND() REALTIME() REALTIME_DESTROY() REALTIME_FIELD() REALTIME_HASH() REALTIME_STORE() RECORDING_INFO() REDIRECTING() REGEX() REPLACE() RTRIM() SAYFILES() SCRAMBLE() SET() SHA1() SHARED() SHELL() SHIFT() SIPPEER() SIP_HEADER() SIP_HEADERS() SMDI_MSG() SMDI_MSG_RETRIEVE() SORT() SPEECH() SPEECH_ENGINE() SPEECH_GRAMMAR() SPEECH_RESULTS_TYPE() SPEECH_SCORE() SPEECH_TEXT() SPRINTF() SQL_ESC() SQL_ESC_BACKSLASHES() SRVQUERY() SRVRESULT() STACK_PEEK() STAT() STIR_SHAKEN() STIR_SHAKEN_ATTESTATION() STRBETWEEN() STRFTIME() STRPTIME() STRREPLACE() SYSINFO() TALK_DETECT() TESTTIME() TIMEOUT() TOLOWER() TONE_DETECT() TOUPPER() TRIM() TRYLOCK() TXTCIDNAME() UNLOCK() UNSHIFT() URIDECODE() URIENCODE() UUID() VALID_EXTEN() VARIABLE_EXISTS() VERSION() VMCOUNT() VM_INFO() VOLUME()
Functions
ABS() AES_DECRYPT() AES_ENCRYPT() AGC() AGENT() AMI_CLIENT() ARRAY() AST_CONFIG() AST_SORCERY() BASE64_DECODE() BASE64_ENCODE() BASENAME() BLACKLIST() CALENDAR_BUSY() CALENDAR_EVENT() CALENDAR_QUERY() CALENDAR_QUERY_RESULT() CALENDAR_WRITE() CALLCOMPLETION() CALLERID() CALLERPRES() CDR() CDR_PROP() CHANNEL() CHANNELS() CHANNEL_EXISTS() CHECKSIPDOMAIN() CONFBRIDGE() CONFBRIDGE_CHANNELS() CONFBRIDGE_INFO() CONNECTEDLINE() CSV_QUOTE() CURL() CURLOPT() CUT() DAHDI_CHANNEL() DB() DB_DELETE() DB_EXISTS() DB_KEYCOUNT() DB_KEYS() DEC() DELETE() DENOISE() DEVICE_STATE() DIALGROUP() DIALPLAN_EXISTS() DIGIT_SUM() DIRNAME() DUNDILOOKUP() DUNDIQUERY() DUNDIRESULT() ENUMLOOKUP() ENUMQUERY() ENUMRESULT() ENV() EVAL() EVAL_EXTEN() EVAL_SUB() EXCEPTION() EXISTS() EXPORT() EXTENSION_STATE() FAXOPT() FEATURE() FEATUREMAP() FIELDNUM() FIELDQTY() FILE() FILE_COUNT_LINE() FILE_FORMAT() FILTER() FRAME_DROP() FRAME_TRACE() GEOLOC_PROFILE() GLOBAL() GLOBAL_DELETE() GLOBAL_EXISTS() GROUP() GROUP_COUNT() GROUP_LIST() GROUP_MATCH_COUNT() HANGUPCAUSE() HANGUPCAUSE_KEYS() HASH() HASHKEYS() HINT() HOLD_INTERCEPT() IAXPEER() IAXVAR() ICONV() IF() IFMODULE() IFTIME() IMPORT() INC() ISNULL() JABBER_RECEIVE() JABBER_STATUS() JITTERBUFFER() JSON_DECODE() KEYPADHASH() LEN() LISTFILTER() LOCAL() LOCAL_PEEK() LOCK() LOG_GROUP() LTRIM() MAILBOX_EXISTS() MASTER_CHANNEL() MATH() MAX() MD5() MEETME_INFO() MESSAGE() MESSAGE_DATA() MIN() MINIVMACCOUNT() MINIVMCOUNTER() MIXMONITOR() MUTEAUDIO() ODBC() ODBC_FETCH() PARK_GET_CHANNEL() PASSTHRU() PERIODIC_HOOK() PITCH_SHIFT() PJSIP_AOR() PJSIP_CONTACT() PJSIP_DIAL_CONTACTS() PJSIP_DTMF_MODE() PJSIP_ENDPOINT() PJSIP_HEADER() PJSIP_HEADERS() PJSIP_HEADER_PARAM() PJSIP_INHERITABLE_HEADER() PJSIP_MEDIA_OFFER() PJSIP_MOH_PASSTHROUGH() PJSIP_PARSE_URI() PJSIP_PARSE_URI_FROM() PJSIP_RESPONSE_HEADER() PJSIP_RESPONSE_HEADERS() PJSIP_SEND_SESSION_REFRESH() PJSIP_TRANSFER_HANDLING() POLARITY() POP() PP_EACH_EXTENSION() PP_EACH_USER() PRESENCE_STATE() PUSH() QUEUE_EXISTS() QUEUE_GET_CHANNEL() QUEUE_MEMBER() QUEUE_MEMBER_COUNT() QUEUE_MEMBER_LIST() QUEUE_MEMBER_PENALTY() QUEUE_VARIABLES() QUEUE_WAITING_COUNT() QUOTE() RAND() REALTIME() REALTIME_DESTROY() REALTIME_FIELD() REALTIME_HASH() REALTIME_STORE() RECORDING_INFO() REDIRECTING() REGEX() REPLACE() RTRIM() SAYFILES() SCRAMBLE() SET() SHA1() SHARED() SHELL() SHIFT() SIPPEER() SIP_HEADER() SIP_HEADERS() SMDI_MSG() SMDI_MSG_RETRIEVE() SORT() SPEECH() SPEECH_ENGINE() SPEECH_GRAMMAR() SPEECH_RESULTS_TYPE() SPEECH_SCORE() SPEECH_TEXT() SPRINTF() SQL_ESC() SQL_ESC_BACKSLASHES() SRVQUERY() SRVRESULT() STACK_PEEK() STAT() STIR_SHAKEN() STIR_SHAKEN_ATTESTATION() STRBETWEEN() STRFTIME() STRPTIME() STRREPLACE() SYSINFO() TALK_DETECT() TESTTIME() TIMEOUT() TOLOWER() TONE_DETECT() TOUPPER() TRIM() TRYLOCK() TXTCIDNAME() UNLOCK() UNSHIFT() URIDECODE() URIENCODE() UUID() VALID_EXTEN() VARIABLE_EXISTS() VERSION() VMCOUNT() VM_INFO() VOLUME()