lslocks Command

Purpose

Displays information about local system file locks that are held by processes.

Syntax

lslocks [ -h ] [ -i ] [ -J ] [ -n ] [ -o list ] [ -p pid ] [ -r ] [ -u ] [ -V ]

Description

The lslocks command displays information about local system file locks that are held by processes. In PowerVC virtual appliance, only read-only inspection of locks is allowed for security. No modification, unlocking, or privileged operations are allowed.

Flags

Table 1. Flags
Items	Description
-h or --help	Displays help about the lslocks command.
-i or --noinaccessible	Skips lock entries that cannot be accessed
-J or --json	Redirects the results in a JSON format for scripting and automation.
-n or --noheadings	Displays the device list without the column headers in a simple format. Then output of this option is ideal for scripting.
-o `list` or --output `list`	Displays lock information only for the specified columns headings. A list of column headers can be specified separated by commas. For more information about the available column headers, see Column headers.
-p `pid` or --pid `pid`	Show locks held by the specified process ID.
-r or --raw	Displays raw output. The output is not aligned. Only minimum formatting is done to the data.
-u or --notruncate	Forces the lslocks command to display the complete information for every column.
-V or --version	Displays version information.

Column headers

The -o parameter is followed by a list of columns that must be displayed in the output. The device information has the following column headings:

Table 2. Column headers
Columns headers	Description
`COMMAND`	Specifies the process name that holds the lock.
`PID`	Specifies the process ID.
`USER`	Specifies the username of the process owner.
`TYPE`	Specifies the lock type. For example, `FLOCK` (flock), `POSIX`, `OFDLCK`.
`MODE`	Specifies the access mode for the lock. For example, `READ`, `WRITE`.
`M`	Specifies the state of the lock. A value of 0 is for advisory lock and a value of `1` is for a mandatory lock.
`START`	Specifies the starting byte offset of the lock.
`END`	Specifies the ending byte offset of the lock. A value of `*` specifies that the whole file is locked.
`PATH`	Specifies the full path of a locked file.
`DEVICE`	Specifies the major and minor device numbers of the file.
`INODE`	Specifies the inode number of the locked file.
`SIZE`	Specifies the capacity of the locked region.

Note: If the lslocks command is used without the -o command, the following columns are displayed in the output:

COMMAND
PID
USER
TYPE
MODE
M
START
END
PATH

Examples

To display the default list of all local locks, enter the following command:
```
lslocks
```
To direct the output to a JSON file, enter the following command:
```
lslocks -J
```
To display locks for a specific PID, enter the following command:
```
lslocks -p <pid>
```
To display only the COMMAND, PID, and PATH columns, enter the following command:
```
lslocks -o COMMAND,PID,PATH
```
To display raw output with complete information and without any column headers, enter the following command:
```
lslocks -r -n -u
```
To display only the accessible locks, enter the following command:
```
lslocks -i
```