lttng-enable-event(1)
=====================
-:revdate: 3 May 2021
+:revdate: 12 May 2021
NAME
[verse]
*lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *enable-event* option:--kernel
(option:--probe='LOC' | option:--function='LOC' | option:--userspace-probe='LOC') 'RECORDNAME'
- [option:--filter='EXPR'] [option:--session='SESSION'] [option:--channel='CHANNEL']
+ [option:--session='SESSION'] [option:--channel='CHANNEL']
Create or enable one or more recording event rules to match
user space tracepoint events:
Without the option:--channel option::
The channel named `channel0`.
+
-If such a channel doesn't exist, the `enable-event` automatically
-creates it.
+If there's already a channel for the selected tracing session and domain
+which isn't named `channel0`, the `enable-event` command fails.
+Otherwise, it automatically creates it.
List the recording event rules of a specific tracing session
and/or channel with the man:lttng-list(1) and man:lttng-status(1)
from the most to the least severe:
User space (option:--userspace option)::
- Shortcuts such as `system` are allowed.
-+
-* `TRACE_EMERG` (0)
-* `TRACE_ALERT` (1)
-* `TRACE_CRIT` (2)
-* `TRACE_ERR` (3)
-* `TRACE_WARNING` (4)
-* `TRACE_NOTICE` (5)
-* `TRACE_INFO` (6)
-* `TRACE_DEBUG_SYSTEM` (7)
-* `TRACE_DEBUG_PROGRAM` (8)
-* `TRACE_DEBUG_PROCESS` (9)
-* `TRACE_DEBUG_MODULE` (10)
-* `TRACE_DEBUG_UNIT` (11)
-* `TRACE_DEBUG_FUNCTION` (12)
-* `TRACE_DEBUG_LINE` (13)
-* `TRACE_DEBUG` (14)
++
+* `EMERG` (0)
+* `ALERT` (1)
+* `CRIT` (2)
+* `ERR` (3)
+* `WARNING` (4)
+* `NOTICE` (5)
+* `INFO` (6)
+* `DEBUG_SYSTEM` (7)
+* `DEBUG_PROGRAM` (8)
+* `DEBUG_PROCESS` (9)
+* `DEBUG_MODULE` (10)
+* `DEBUG_UNIT` (11)
+* `DEBUG_FUNCTION` (12)
+* `DEBUG_LINE` (13)
+* `DEBUG` (14)
`java.util.logging` (option:--jul option)::
- Shortcuts such as `severe` are allowed.
-+
-* `JUL_OFF` (`INT32_MAX`)
-* `JUL_SEVERE` (1000)
-* `JUL_WARNING` (900)
-* `JUL_INFO` (800)
-* `JUL_CONFIG` (700)
-* `JUL_FINE` (500)
-* `JUL_FINER` (400)
-* `JUL_FINEST` (300)
-* `JUL_ALL` (`INT32_MIN`)
++
+* `OFF` (`INT32_MAX`)
+* `SEVERE` (1000)
+* `WARNING` (900)
+* `INFO` (800)
+* `CONFIG` (700)
+* `FINE` (500)
+* `FINER` (400)
+* `FINEST` (300)
+* `ALL` (`INT32_MIN`)
Apache log4j (option:--log4j option)::
- Shortcuts such as `severe` are allowed.
+
-* `LOG4J_OFF` (`INT32_MAX`)
-* `LOG4J_FATAL` (50000)
-* `LOG4J_ERROR` (40000)
-* `LOG4J_WARN` (30000)
-* `LOG4J_INFO` (20000)
-* `LOG4J_DEBUG` (10000)
-* `LOG4J_TRACE` (5000)
-* `LOG4J_ALL` (`INT32_MIN`)
+* `OFF` (`INT32_MAX`)
+* `FATAL` (50000)
+* `ERROR` (40000)
+* `WARN` (30000)
+* `INFO` (20000)
+* `DEBUG` (10000)
+* `TRACE` (5000)
+* `ALL` (`INT32_MIN`)
Python (option:--python option)::
- Shortcuts such as `critical` are allowed.
+
-* `PYTHON_CRITICAL` (50)
-* `PYTHON_ERROR` (40)
-* `PYTHON_WARNING` (30)
-* `PYTHON_INFO` (20)
-* `PYTHON_DEBUG` (10)
-* `PYTHON_NOTSET` (0)
+* `CRITICAL` (50)
+* `ERROR` (40)
+* `WARNING` (30)
+* `INFO` (20)
+* `DEBUG` (10)
+* `NOTSET` (0)
[[filter-cond]]
condition of a recording event rule if the option:--filter='EXPR'
option is missing or if 'EXPR' is _true_.
+This condition is only meaningful for the LTTng tracepoint and Linux
+system call instrumentation point types: it's always satisfied for other
+types.
+
'EXPR' can contain references to the payload fields of{nbsp}__E__ and
to the current context fields.
option:-f 'EXPR', option:--filter='EXPR'::
Only match events of which 'EXPR', which can contain references to
event payload and current context fields, is _true_.
++
+This option is only available with the option:--tracepoint or
+option:--syscall option.
include::common-lttng-cmd-help-options.txt[]