Question

To feed standard output of one command to standard input of another in a single shell session, which of the following can be used?

1) IO redirection
2) Named pipes
3) The pipe operator provided by the shell

Answer 1

To feed the standard output of one command to the standard input of another, the pipe operator, IO redirection, and named pipes can be used. The pipe operator is the most straightforward method for command chaining in shell sessions.

Step-by-step explanation:

Using Command-Line Operators for Input and Output Redirection

To feed the standard output of one command to the standard input of another in a single shell session, you can use several methods. The most common and straightforward method is using the pipe operator (|) provided by the shell. For example, command1 | command2 would take the output from command1 and use it as the input for command2.

Another option is IO redirection. This involves using operators like > for output redirection and < for input redirection. For example, command1 > file would write the output of command1 into a file, and command2 < file would read the input for command2 from a file.

Named pipes, also known as FIFOs, can also be used for this purpose. A named pipe is created with the mkfifo command, and it allows for a unidirectional flow of data between two processes. This is less common for simple command chaining but can be useful in more complex scenarios.