1e41f4b71Sopenharmony_ci# dmesg 2e41f4b71Sopenharmony_ci 3e41f4b71Sopenharmony_ci 4e41f4b71Sopenharmony_ci## Command Function 5e41f4b71Sopenharmony_ci 6e41f4b71Sopenharmony_ciThis command is used to display system boot and running information. 7e41f4b71Sopenharmony_ci 8e41f4b71Sopenharmony_ci 9e41f4b71Sopenharmony_ci## Syntax 10e41f4b71Sopenharmony_ci 11e41f4b71Sopenharmony_cidmesg 12e41f4b71Sopenharmony_ci 13e41f4b71Sopenharmony_cidmesg [_-c/-C/-D/-E/-L/-U_] 14e41f4b71Sopenharmony_ci 15e41f4b71Sopenharmony_cidmesg -s [_size_] 16e41f4b71Sopenharmony_ci 17e41f4b71Sopenharmony_cidmesg -l [_level_] 18e41f4b71Sopenharmony_ci 19e41f4b71Sopenharmony_cidmesg > [_fileA_] 20e41f4b71Sopenharmony_ci 21e41f4b71Sopenharmony_ci 22e41f4b71Sopenharmony_ci## Parameters 23e41f4b71Sopenharmony_ci 24e41f4b71Sopenharmony_ci**Table 1** Parameter description 25e41f4b71Sopenharmony_ci 26e41f4b71Sopenharmony_ci| Parameter | Description | Value Range | 27e41f4b71Sopenharmony_ci| --------------- | ---------------------------------------- | --------------- | 28e41f4b71Sopenharmony_ci| -c | Prints content in the buffer and clears the buffer. | N/A | 29e41f4b71Sopenharmony_ci| -C | Clears the buffer. | N/A | 30e41f4b71Sopenharmony_ci| -D/-E | Disables or enables printing to the console. | N/A | 31e41f4b71Sopenharmony_ci| -L/-U | Disables or enables printing via the serial port. | N/A | 32e41f4b71Sopenharmony_ci| -s size | Sets the size of the buffer. size specifies the buffer size to set.| N/A | 33e41f4b71Sopenharmony_ci| -l level | Sets the buffering level. | [0, 5] | 34e41f4b71Sopenharmony_ci| > fileA | Writes the content in the buffer to a file. | N/A | 35e41f4b71Sopenharmony_ci 36e41f4b71Sopenharmony_ci 37e41f4b71Sopenharmony_ci## Usage Guidelines 38e41f4b71Sopenharmony_ci 39e41f4b71Sopenharmony_ci- This command can be used only after **LOSCFG_SHELL_DMESG** is enabled. To enable **LOSCFG_SHELL_DMESG**, run the **make menuconfig** command in **kernel/liteos_a**. In the displayed dialog box, locate the **Debug** option and set **Enable Shell dmesg** to **Yes**. 40e41f4b71Sopenharmony_ci Debug ---> Enable a Debug Version ---> Enable Shell ---> Enable Shell dmesg 41e41f4b71Sopenharmony_ci 42e41f4b71Sopenharmony_ci- If no parameter is specified, all content in the buffer is printed. 43e41f4b71Sopenharmony_ci 44e41f4b71Sopenharmony_ci- The parameters followed by hyphens (-) are mutually exclusive. 45e41f4b71Sopenharmony_ci 1. Before writing content to a file, ensure that the file system has been mounted. 46e41f4b71Sopenharmony_ci 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. 47e41f4b71Sopenharmony_ci 48e41f4b71Sopenharmony_ci 49e41f4b71Sopenharmony_ci## Example 50e41f4b71Sopenharmony_ci 51e41f4b71Sopenharmony_ciRun **dmesg> dmesg.log**. 52e41f4b71Sopenharmony_ci 53e41f4b71Sopenharmony_ci 54e41f4b71Sopenharmony_ci## Output 55e41f4b71Sopenharmony_ci 56e41f4b71Sopenharmony_ciWrite the content in the buffer to the **dmesg.log** file. 57e41f4b71Sopenharmony_ci 58e41f4b71Sopenharmony_ci``` 59e41f4b71Sopenharmony_ciOHOS # dmesg > dmesg.log 60e41f4b71Sopenharmony_ciDmesg write log to dmesg.log success 61e41f4b71Sopenharmony_ci``` 62