dmesg

Command Function

This command is used to display system boot and running information.

Syntax

dmesg

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

dmesg -s [size]

dmesg -l [level]

dmesg > [fileA]

Parameters

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

Disables or enables printing to the console.

N/A

-L/-U

Disables or enables 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 the specified file.

N/A

Usage

  • 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 no parameter is 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 shell. You are advised to set up a connection using Telnet before disabling the serial port.

Example

Run dmesg> dmesg.log.

Output

Writing the content in the buffer to the dmesg.log file:

OHOS # dmesg > dmesg.log
Dmesg write log to dmesg.log success