dmesg

Command Function

This command is used to control the dmesg buffer of the kernel.

dmesg

dmesg [-c/-C/-D/-E/-L/-U]

dmesg -s [size]

dmesg -l [level]

dmesg > [fileA]

Table 1 Parameter description

Parameter	Description	Value Range
-c	Prints content in the buffer and clears the buffer.	N/A
-C	Clears the buffer.	N/A
-D/-E	Enables or disables printing to the console.	N/A
-L/-U	Enables or disables printing via the serial port.	N/A
-s size	Sets the size of the buffer.	N/A
-l level	Sets the buffering level.	0 - 5
> fileA	Writes the content in the buffer to a file.	N/A

This command depends on LOSCFG_SHELL_DMESG. Before using this command, select Enable Shell dmesg on menuconfig.

Debug ---> Enable a Debug Version ---> Enable Shell ---> Enable Shell dmesg
If the parameters are not specified, all content in the buffer is printed.
The parameters followed by hyphens (-) are mutually exclusive.
1. Before writing content to a file, ensure that the file system has been mounted.
2. Disabling the serial port printing will adversely affect the shell. You are advised to set up a connection using Telnet before disabling the serial port.

Example:

Run dmesg > /usr/dmesg.log.

Figure 1 Writing dmesg content to a file