sem
Command Function
This command is used to query information about kernel semaphores.
Syntax
sem [ID_ / fulldata_]
Parameters
Table 1 Parameter description
Queries information about all the semaphores in use. The information to be printed includes SemID, Count, OriginalCount, Creater(TaskEntry), and LastAccessTime. |
Usage
-
If the parameters are not specified, this command displays the number of used semaphores and the total number of semaphores.
-
If the ID parameter is specified, semaphores of the specified ID are displayed.
-
The fulldata parameter depends on LOSCFG_DEBUG_SEMAPHORE. Before using this parameter, select Enable Semaphore Debugging on menuconfig.
Debug ---> Enable a Debug Version ---> Enable Debug LiteOS Kernel Resource ---> Enable Semaphore Debugging
Example
Run sem fulldata.
Output
Figure 1 Querying information about all semaphores in use
Table 2 Output
NOTE: The ID value can be in decimal or hexadecimal format. When the ID value is within the range of [0, 1023], semaphore information of the specified ID is displayed. If the semaphore ID is not used, a message is displayed to inform you of this case. For other values, a message is displayed indicating that the parameter is incorrect.