1# format 2 3 4## Command Function 5 6This command is used for disk formatting. 7 8 9## Syntax 10 11format <*dev*inodename_> <*sectors*> <*option*> [_label_] 12 13 14## Parameters 15 16**Table 1** Parameter description 17 18| Parameter| Description| 19| -------- | -------- | 20| dev_inodename | Specifies the device name. | 21| sectors | Specifies the size of the allocated memory unit or sector. <br/>The value must be **0** or a power of **2**.<br/>The value **0** means to leave this parameter blank. <br/>For FAT32, the maximum value is **128**. If the parameter is set to **0**, a proper cluster size is automatically selected. The available cluster size range varies depending on the partition size. If the cluster size is incorrectly specified, the formatting may fail. | 22| option | Specifies the file system type. The options are as follows:<br>- **0x01**: FMT_FAT<br>- **0x02**: FMT_FAT32<br>- **0x07**: FMT_ANY<br>- **0x08**: FMT_ERASE (USB does not support this option.)<br>If an invalid value is specified, the system automatically selects the formatting mode. If the low-level formatting bit is **1** during the formatting of a USB flash drive, an error message is printed.| 23| label | Specifies the volume label name. This parameter is optional, and the value is a string. <br/>If **null** is specified for this parameter, the previously set volume label name is cleared. | 24 25 26## Usage Guidelines 27 28- The **format** command is used for disk formatting. You can find the device name in the **dev** directory. A storage card must be installed before the formatting. 29 30- The **format** command can be used to format the USB flash drive, SD card, and MMC, but not the NAND flash or NOR flash. 31 32- An invalid **sectors** value may cause exceptions. 33 34 35## Example 36 37Run **format /dev/mmcblk0 128 2**. 38 39 40## Output 41 42Format an MMC. 43 44``` 45OHOS # format /dev/mmcblk1 128 2 46Format to FAT32, 128 sectors per cluster. 47format /dev/mmcblk1 Success 48``` 49