History command, Linux

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A command shell built-in function available on Linux platforms; used to modify, display or delete the command history list.

Usage Syntax

history [options]

Common options include;

number - only display the specified number of most recent command history list entries
-c - clear the entire command history list
-d line_number - delete the command history list entry specified by line_number
-a filename - append the command history list for the current session only to the file specified by filename
-r filename - read the contents of the specified filename and use them as the command history list

Usage Examples

history 10 - display the 10 most recent entries in the command history list

history -d 132 - delete the command history list entry with line number 132

history -c - delete the entire command history list

Usage Notes

Most shells support a number of command history related Shell Expansion Characters

Use font color=limegreen!n/font to insert the text of the command history list line number n at the command line

Use font color=dodgerblue[CTRL]/font+font color=limegreenR/font to search the command history list

BASH will auto-complete the first command matching the text you enter. Repeat font color=dodgerblue[CTRL]/font+font color=limegreenR/font to display the next command history match

Use font color=lightslategray[RETURN]/font to execute the command or, to cancel: font color=darkcyan[ESC]/font or font color=dodgerblue[CTRL]/font+font color=limegreenC/font

See our Linux CLI Masterclass for more information on information on effective and efficient use of the command line.

Related Files

The default bash history file location is here: ~/.bash_history

Security Considerations

Using any commands or associated options or parameters that include password presents a security risk as any users with read access to your command history list file ~/.bash_history will be able obtain the password. Either;

Avoid specifying a password with the command (if the program can prompt instead)
Clear the entire history list using history -c
Remove the specific command from the history list using history -d line_number

Linux Usage Notes

With most Linux or Unix commands;

Non root users may need to prefix commands with the sudo command, for example: sudo chmod 644 *
Brief help can be displayed using the -h or --help parameter, for example: chmod --help
A full command manual can be displayed using the man command followed by the command name, for example: man chmod
Sometimes 'info' pages are used instead of or to provide more information than man pages; for example: info chmod
Version information can normally be display using the -v, -V or --version parameter, for example: chmod --version. However, this paramater is also frequently used to display verbose output.