Dos supports the following control operator in order to control or separate command instruction.
For a linux shell, see What are Control Operators in Bash?
| Operator | Description |
|---|---|
| & | all commands run serially without error checking |
| && | execute the next command only if the previous command is successful |
| || | execute the next command only executed only if the previous command has failed |
| () | group commands |
The command following && is executed only if the first command is successful. This will work only with a command used before && that returns an exit code of 0 (zero).
echo 1 && echo 2
1
2
& error checking is not performed and all commands run serially.
badcommand 2>null & echo 1 & echo 2
1
2
where:
The OR control operator
||. The command following && is executed only if the first command has failed. This will work only with a command used before && that returns an exit code that is not `0' (zero).
echo 1 || echo 2
1
Group command
(echo 1 && echo 2)