Sob o bash, você pode criar uma seqüência de um ou mais comandos separados por um dos seguintes operadores:
| Operator | Syntax | Description | Example |
|---|---|---|---|
| ; | command1; command2 | Separates commands that are executed in sequence. |
In this example, pwd is executed only after date command completes.date ; pwd |
| & | command arg & | The shell executes the command in the background in a subshell. The shell does not wait for the command to finish, and the return status is 0. The & operator runs the command in background while freeing up your terminal for other work. |
In this example, find command is executed in background while freeing up your shell prompt.find / -iname "*.pdf" >/tmp/output.txt & |
| && | command1 && command2 | command2 is executed if, and only if, command1 returns an exit status of zero i.e. command2 only runs if first command1 run successfully. |
[ ! -d /backup ] && mkdir -p /backupSee Logical AND section for examples. |
| || | command1 || command2 | command2 is executed if and only if command1 returns a non-zero exit status i.e. command2 only runs if first command fails. |
tar cvf /dev/st0 /home || mail -s 'Backup failed' you@example.com </dev/nullSee Logical OR section for examples. |
| | | command1 | command2 | Linux shell pipes join the standard output of command1 to the standard input of command2. |
In this example, output of the ps command is provided as the standard input to the grep commandps aux | grep httpd |
