I want 3 UNIX command which use neither standard input nor standard output .

I am still confused that a command with any redirection of using pipes is can be said as a example of not using standard input or standard output

CodePudding user response：

"standard input" is normally what comes from the user's keyboard, or in the case of a pipeline, what comes from the preceding process.

"standard output" is normally what gets sent to the screen, or in the case of a pipeline, what gets sent onto the following process.

So, you seem to be looking for commands that read no input, and produce no output. Here are some that spring to mind:

• cd
• touch
• mkdir
• nice
• shutdown
• true
• false