In Linux, the redirection operator is a special character used to control the input and output streams of commands and shell scripts. It allows users to redirect input from and output to files, devices, or other commands. The redirection operator is primarily used in the command line interface (CLI) and shell scripts to manipulate input and output streams efficiently.
Here are the common redirection operators used in Linux :Standard Output Redirection (>) : The
> operator is used to redirect the standard output (
stdout) of a command to a file or device. If the specified file already exists, it will be overwritten. If it does not exist, a new file will be created.
command > output.txt?
Append Output Redirection (>>) : The
>> operator is similar to
>, but it appends the output of a command to the specified file instead of overwriting it. If the file does not exist, a new file will be created.
command >> output.txt?
Standard Input Redirection (<) : The
< operator is used to redirect the standard input (
stdin) of a command from a file. It allows the command to read input from the specified file instead of from the keyboard.
command < input.txt?
Here Document (<<) : The
<< operator is used to create a temporary input stream for a command. It allows multiple lines of input to be provided directly within the shell script without the need for an external file.
command << EOF
This is line 1
This is line 2
EOF?
Here String (<<<) : The
<<< operator is used to redirect a string as input to a command. It allows a string to be passed as input to a command without the need for an external file or here document.
command <<< "input string"?
Pipe (|) : The
| operator is used to redirect the standard output (
stdout) of one command as the standard input (
stdin) of another command. It allows the output of one command to be passed as input to another command.
command1 | command2?
These redirection operators provide powerful capabilities for manipulating input and output streams in Linux, allowing users to efficiently manage data flow in command line operations and shell scripts.
