最後更新: 2020-08-10
介紹
exec command in Linux is used to execute a command from the bash itself.
This command does not create a new process it just replaces the bash with the command to be executed.
If the exec command is successful, it does not return to the calling process.
Usage
Syntax
exec [-cl] [-a name] [command [arguments]] [redirection ...]
Options
- c: It is used to execute the command with empty environment.
- a name: Used to pass a name as the zeroth argument of the command.
- l: Used to pass dash as the zeroth argument of the command.
The exec command can be used in two modes:
- Exec with a command as an argument: exec ls
-
Exec without a command: exec > log.txt
# The redirections can be used to modify the current shell environment.
Usage - redirect STDIN, STDOUT, STDERR
exec 0< '/dev/null' exec 1> '/dev/null' exec 2> '/dev/null'