Descriptions of the system utilities are contained in the following pages of this section. System Utilities are summarized in Table 3-1.
Name
Alter the size of the swap space on a block device.
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 inconsistencies 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.
SYSTEM UIIUTIES adduser
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 perfonns the following tasks:
1. Adds the new name to the end of the password file, letc/log/password.
2. Assigns a user ID to the user.
3. Creates a home directory owned by the new user with rwxr-x pennissions. The name of this directory is I<user _name>.
4. Copies the default .shellbegin file into the user's home directory and creates empty .login and .shellhistory files.
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
Tnis exampie adds the user name chris to the bottom of the file letc/log/password, assigns a user 10, and creates the directory /chris, 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 1< 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 returned an error when adduser tried to create the file 1< 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 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 returned by the operating system.
Name must be 1 to 8 lowercase letters.
The specified user name must be from one to 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
SYSTEM UTIUTIES aIterswap
alterswap
Alters the size of the swap space on a block device.
SYNTAX
alterswap <dev name> [+pqr]
DESCRIPTION
The alterswap command can alter the size of the swap space on a block device. The user may specify the new size as an increase, decrease, or absolute value. The size may be specified as either blocks or K-bytes. If the value specified is a pure number, it is assumed to be a block count. If the value is a number with the letter 1(' appended, the size is taken to be a K-byte count. The program will prompt for all necessary information as it runs. See help on diskrepair.
ARGUMENTS
<dev name> The name of the device to alter; must be a block device.
OPTIONS
q v
diskrepair will prompt for action on each reported error.
diskrepair in quiet mode, inhibits certain messages and warnings.
diskrepair in verbose mode, all errors are always reported.
EXAMPLES
alterswap /dev/floppy +p
This example would request alterswap to alter the swap size on device Idevlfloppy. When completed, diskrepair would be run in prompt mode. The program prompts the user for all necessary information.
NOTES
• If alterswap is run on the root device, all tasks will be suspended while the program is running. If the swap size is actually changed, the system will shut down upon completion of diskrepair and will need rebooting.
• If alterswap is run on a mounted device, the device will be unmounted prior to alteration.
The device will remain unmounted after t..'le com.-na...d tenninates.
• There are situations in which alterswap cannot alter the size of the swap space. These situations result from the fullness of the existing file system. If this situation happens, the only solution is to reformat the disk and rebuild the file system.
MESSAGES
Freezing all system tasks ...
The program is altering the swap space of the root device and must suspend all tasks before proceeding.
Running diskrepair ...
The program" diskrepair" is now being run to rebuild the disk.
Sizing disk ...
The program is reading the device to determine its structure. This may be time consuming, depending on the size of the device.
ERROR MESSAGES
Error opening "<device name>": <reason>
The operating system returned an error when alterswap tried to open the specified device. This message is followed by an interpretation of the error returned by the operating system.
Error seeking on "<device_name>": <reason>
The operating system returned an error when alterswap tried to seek on the specified device.
This message is followed by an interpretation of the error returned by the operating system.
Only the system manager may alter swap space.
The alterswap command may only be used by the system manager.
SEE ALSO
diskrepair
SYSTEM UTILITIES badblocks
badblocks
Removes bad disk blocks from the free list on the specified device.
SYNTAX
letc/badblocks <dey name> <block number> [+dpqsv] [+m=<address>]
DESCRIPTION
Removes bad disk blocks from the free list on the specified device. The bad block infonnation is recorded in the file I.badblocks. Once the bad block infonnation is recorded, the diskrepair utility is run to check the file system integrity. Bad blocks are identified by the devcheck utility, whichs reports the bad blocks by decimal and HEX block number. Be warned - badblocks expects the bad block number to be in decimal radix! 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 refonnat and rebuild will utilize the controller option to mask out bad blocks. See help on devcheck and diskrepair.
ARGUMENTS
<dev name>
<bad block list> -
-<block number>
OPTIONS
The name of the device to check; must be a block device.
The list of bad block numbers in decimal radix! If a floppy diskette contains one or more bad blocks it should be discarded.
The number of the bad block in decimal radix.
This utility has the same options as diskrepair.
d Do not run diskrepair.
The address to use for mapping.
Prompt user for pennission to correct diskrepair errors.
Run diskrepair in quiet mode.
Ignore SIR (System Information Record) information in derennining disk size; this allows one to repair a disk with a corrupted SIR.
Run diskrepair in verbose mode.
blockcheck
Check the integrity of all block allocations used in files and of the free list on the specified device.
SYNTAX
/etc/blockcheck <dev name>
DESCRIPTION
The blockcheck command 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 diskrepair utility, which calls it. It may also be used on its own as a diagnostic utility; however, blockcheck can only inspect the disk; it cannot repair it. If blockheck's output suggests that the disk is damaged, use diskrepair 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 all the block allocations on the floppy disk.
SEE ALSO
devcheck diskrepair fdncheck
SYSTEM UTILITIES deluser
deluse
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 JetC/logJpassword and by default removes all 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 JetC/log/password. It also deletes all files and subdirectories in the directory /chris, as well as that directory itself.
CAUTION