Shell Commands
A simple shell command such as echo a b c consists of the command itself followed by arguments, separated by spaces.
More complex shell commands are composed of simple commands arranged together in a variety of ways: in a pipeline in which the output of one command becomes the input of a second, in a loop or conditional construct, or in some other grouping.
| • Simple Commands: | The most common type of command. | |
| • Pipelines: | Connecting the input and output of several commands. | |
| • Lists: | How to execute commands sequentially. | |
| • Compound Commands: | Shell commands for control flow. | |
| • Coprocesses: | Two-way communication between commands. | |
| • GNU Parallel: | Running commands in parallel. |