Android Super Terminal commands (II)-Installation and logon commands

Reboot

1. Role

The reboot command is used to restart the computer. Its permission is assigned to the system administrator.

2. Format

　　Reboot [-N] [-W] [-D] [-F] [-I]

3. Main Parameters

-N: Do not write the memory data back to the hard disk before restarting the instance.

-W: The record is not written to the/var/log/wtmp file.

-D: Do not write the record to the/var/log/wtmp file (the-n parameter contains-D ).

-I: Stop all network-related devices before restarting.

 

Mount

1. Role

The mount command is used to load the file system. Its permission is granted to a Super User or a user allowed in/etc/fstab.

2. Format

Mount-A [-FV] [-T vfstype] [-N] [-RW] [-F] device dir

3. Main Parameters

-H: displays the auxiliary information.

-V: display information, usually used with-F for debugging.

-A: Mount all file systems defined in/etc/fstab.

-F: this command is usually used with-a, which generates a route for each Mount action. It can speed up loading when the system needs to mount a large number of NFS file systems.

-F: usually used for debugging. It causes mount to not execute the actual mounting action, but simulate the entire mounting process, which is usually used together with-v.

-T vfstype: displays the type of the file system to be loaded.

-N: In general, after Mount is mounted, a piece of data will be written to the/etc/mtab. You can use this option to cancel this operation if the system does not have the file system to write data.

4. Application Skills

On Linux and Unix systems, all files are accessed as part of a large tree (with/as the root. To access files on a CD-ROM, You need to mount the CD-ROM device to a mount point in the file tree. If the release version is installed with an automatic mounting package, this step can be performed automatically. In Linux, if you want to use storage devices such as hard disks and optical drives, you must load them first. After the storage devices are mounted, you can use them as a directory for access. Mount a device and run the mount command. When using the mount command, you must first know the following three types of information: file system type of the object to be loaded, device name of the object to be loaded, and directory to which the device is to be loaded.

(1) recognizable file systems in Linux

◆ Windows 95/98 common FAT 32 File System: vfat;

◆ Win NT/2000 File System: NTFS;

◆ OS/2 File System: HPFs;

◆ Linux File Systems: ext2 and ext3;

◆ CD-ROM disc File System: iso9660.

Although vfat is a FAT 32 system, it is actually compatible with the file system type of fat 16.

(2) determine the device name

In Linux, device names are usually stored in/dev. These device names are named in a regular way. You can use the "inference" method to find the device names. For example, the/dev/hda1 ide device, HD is hard disk (hard disk), SD is SCSI device, FD is floppy device (or floppy
Disk ?). A Indicates the first device. Generally, the IDE interface can be connected to four ide devices (such as four hard disks ). Therefore, the methods to identify IDE Hard Disks are hda, HDB, HDC, and HDD. " 1" It indicates the first hard disk partition of hda, hda2 indicates the second primary partition of hda, and the first logical partition starts from hda5. In addition, you can directly check the/var/log/messages file to find the device code identified by the system after the computer is started.

(3) Find the mount point

Before deciding to connect the device, check whether the computer has an empty/mnt Directory, which is used as a mount point directory. We recommend that you create several/mnt/CDROM,/mnt/floppy,/mnt/Mo directories in/mnt as dedicated mount points for the directories. For example, if you want to mount the following five devices, the execution command may be as follows (assuming that all are Linux ext2 systems, and if it is Windows XX, change ext2 to vfat ):

Floppy Disk ==> Mount-T ext2/dev/fd0/mnt/floppy

CDROM ==> Mount-T iso9660/dev/HDC/mnt/CDROM

Scsi cdrom ==> Mount-T iso9660/dev/sdb/mnt/content Rom

Scsi cdr ==> Mount-T iso9660/dev/SDC/mnt/scdr

However, most of the latest Linux releases (including Red Flag Linux, mid-soft Linux, and Mandrake Linux) can automatically mount the file system, except Red Hat Linux.

Umount

1. Role

The umount command is used to uninstall a file system. Its permission is granted to a Super User or a user allowed in/etc/fstab.

2. Format

Unmount-A [-ffnrsvw] [-T vfstype] [-N] [-RW] [-F] device dir

3. Instructions for use

The umount command is the inverse operation of the mount command. Its Parameters and usage are the same as those of the mount command. After the Linux mounted CD-ROM, The CD-ROM is locked so that it cannot be popped up with the eject button on the CD-ROM panel. However, if you no longer need a CD, use umount/CDROM to uninstall it if you have used/CDROM as a symbolic link. This command is successful only when no user is using the CD. This command includes a terminal window that uses the current working directory as the directory in the CD.

Exit

1. Role

The exit command exits the system and has the permission to all users.

2. Format

Exit

3. Parameters

The exit command has no parameters. After running the command, exit the system and enter the logon interface.