Descriptions of the system utilitys are contained in the following pages of this section. System Utilities are sumarized in Table 3-1.
Name
remove bad disk blocks from the free list on the specified device check the integrity of the allocation of all blocks used in files and of the free list of the specified device
remove a user from the system check a device for 110 errors
check and, optionally, repair inconsistancies in the logical structure of the disk
check the integrity of the structure of the file descriptor nodes (fdns) on the specified disk
create a special type of file, representing a device
insert a block device at a node of the directory tree structure change the owner of a file
unmount a previously mounted device from the file system
adduser
Add a new user to the system.
SYNTAX
/etc/adduser <user name>
DESCRIPTION
The adduser command is used to add a new user to the system. The specified user name must be unique to the system. It must be between one and eight letters long. All letters must be lower-case. Only the system user may invoke this command.
The adduser command performs the following tasks:
1. Adds the new name to the end of the password me, fetcllogfpassword.
2. Assigns a user ID to the user.
3. Creates a home directory owned by the new user with rwxr.;x permissions. The name of this directory is I<user _name>.
4. Copies the file default .shellbegin file into the user's home directory and creates empty .login and .shellhistory meso
The system user or the new user should use the password command to ensure protection of the new user's files.
ARGUMENTS
<user name>
EXAMPLES
A unique name assigned to the new user for use in response to the login prompt.
/etc/adduser chris
This example adds the user name chris to the bottom of the file fete/logfpassword, assigns a user ID, and creates the directory fchris, which is owned by chris. The permissions in this directory for the owner is read, write and execute, while for others it is read and execute (rwxr-x).
ERROR MESSAGES
Error adding <user_name> to password file: <reason>
The operating system returned an error when adduser tried to add <user_name> to the password file. This message is followed by an interpretation of the error returned by the operating system.
Error assigning owner to /<user_name>: <reason>
The operating system returned an error when adduser tried to make the specified user the owner of the file / < user_name>. This message is followed by an interpretation of the error returned by the operating system.
Error creating /<user_name>: <reason>
The operating system reblrned an error when adduser tried to create the file I<user _name>. This message is followed by an interpretation of the error returned by the operating system.
Error creating . file: <reason>
The operating system returned an error when adduser tried to create the file " This message is followed by an interpretation of the error reblmed by the operating system.
Error creating .. file: <reason>
The operating system returned an error when adduser tried to create the file '" This message is followed by an interpretation of the error reblmed by the operating system.
Name must be 1 to 8 lowercase letters.
The specified user name must be between one and eight letters long. All letters must be lowercase.
Syntax: /etc/adduser <user_name>
The adduser command expects exactly one argument. This message indicates that the argument count is wrong.
The name <user_name> is already in use.
The specified user name must be unique to the system.
You must be system manager to run adduser.
Only the system user may execute the adduser command.
SEE ALSO
deluser password perms
badblocks
Removes bad disk blocks from the free list on the specified device.
SYNTAX
/etc/badblocks <dev name> <block number> [options]
DESCRIPTION
Removes bad disk blocks from the free list on the specified device. The bad block information is recorded in the file I.badblocks. Once the bad-block infonnation is recordedt the diskrepair utility is run to check the file system integrity. Bad blocks are identified by the devcheck utilityt whichs repons the bad-blocks by HEX block numbert badblocks expects the bad-block number to be in decimal radixt be warned! Hard-disks utilize the controller option to mask out bad-blocks so the I.badblocks file is initially empty. Should blocks become defective they are masked out by software via the badblocks utility. Total system reformat and rebuild will utilize the controller option to mask out bad-blocks.
ARGUMENTS
<dev name>
<block number>
OPTIONS
The name of the device to check, must be a block device.
The number of the bad block in decimal radix! If a diskette contains one or more bad blocks it should be discarded.
This utility has the same options as diskrepair.
SEE ALSO
diskrepair
blockcheck
Check the integrity of the allocation of all blocks used in files and of the free list on the specified device.
SYNTAX
/etc/blockcheck <dev name>
DESCRIPTION
blockcheck checks the integrity of the block allocation used in the files and free list on the specified device. It locates problems such as duplicate blocks, missing blocks, and invalid block addresses.
This command is primarily intended for use by the dislcrepair utility, which calls it. It may also be used on its own as a diagnostic utility; however, blockcheck can only check the disk; it cannot repair it. If blockheck's output suggests that the disk is damaged, use dislcrepair on the disk.
You should only use blockcheck if no other tasks are active on the system; otherwise, the results are unpredictable.
ARGUMENTS
<dev name> The name of the device to check. It must be a block device.
EXAMPLES
/etc/blockcheck /dev/floppy
This example checks the integrity of the the allocation of blocks on the floppy disk.
SEE ALSO
devcheck diskrepair fdncheck
deluser
Remove a user from the system.
SYNTAX
/etc/deluser <user name> [+x]
DESCRIPTION
The deluser command removes the specified user from the system. It removes the corresponding entry from the file Jete/log/password and by default destroys files and subdirectories in the user's home directory that are owned by that user. It also deletes the home directory itself if it is empty after all the deletions are complete. Only the system user may execute this command.
ARGUMENTS
<user name> The name of the user to delete from the system.
OPTIONS
x Delete the user, but do not delete the user's files from the system.
EXAMPLES
/etc/deluser chris
This example deletes the line containing the entry for the user name chris from the file /etcllog/password. It also deletes all files and subdirectories in the directory /chris, as well as that directory itself.