View source for Mkfifo: how it works (en)

'''mkfifo''' stands for '''make first-in-first-out'''. It is a command in Unix-based operating systems like Ubuntu that is used to create a *named pipe*. A pipe is an inter-process communication mechanism that allows one process to write data into the pipe while another process reads that data.

==Difference between `mkfifo` and a regular pipe:==

* '''Regular pipe:''' Created dynamically when two processes communicate and disappears once the communication ends.
* '''Named pipe:''' Permanently created in the file system, allowing different processes to access it at any time as long as the pipe exists.

==Why Use `mkfifo`?==

* '''Inter-process communication:''' Ideal for connecting two or more independently running programs.
* '''Synchronization:''' Can be used to synchronize activities between processes.
* '''Gradual data processing:''' Data can be written and read incrementally, allowing for more efficient data processing.

==How to Use `mkfifo`==

===Creating a named pipe:===

 mkfifo pipe_name

Example:

 mkfifo mypipe

The above command creates a named pipe called `mypipe` in the current directory.

===Accessing a named pipe:===

* '''Reading from the named pipe:'''

 cat < pipe_name

* '''Writing to the named pipe:'''

 echo "Hello" > pipe_name

===Usage Example:===

Suppose we have two scripts:

* '''Script 1 (writer):'''

  #!/bin/bash
  while true; do
      echo "Data from script 1" > mypipe
      sleep 1
  done

* '''Script 2 (reader):'''

  #!/bin/bash
  while true; do
      read line < mypipe
      echo "Received data: $line"
  done

Script 1 will continuously write data to `mypipe` every second, while script 2 will continuously read data from `mypipe` and display it on the screen.

==Additional `mkfifo` Options==

* '''`-m mode`:''' Set the access permissions for the named pipe.
* '''`-Z context`:''' Set the SELinux security context for the named pipe.

==Real-World Use Cases==

* '''Transferring data between two programs:''' For example, redirecting output from one program to the input of another.
* '''Implementing a simple queue:''' Data written to the named pipe will be processed sequentially by the reading process.
* '''Communication between parent and child processes:''' The child process can read commands from the parent process through a named pipe.

==Conclusion==

'''mkfifo''' is a highly useful tool for building more complex and efficient systems on Ubuntu Server. By understanding how it works, you can leverage it for various purposes, from inter-process communication to implementing synchronization mechanisms.

==Interesting Links==

* [[Forensic: IT]]