Created SC1132 (markdown)

Vidar Holen
2018-06-16 12:41:00 -07:00
parent 27eff07a21
commit 63ecd1aa3e

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## This `&` terminates the command. Escape it or add space after `&` to silence.
### Problematic code:
```sh
curl https://www.google.com/search?q=cats&tbm=isch
```
### Correct code:
```sh
curl "https://www.google.com/search?q=cats&tbm=isch"
```
### Rationale:
An unescaped and unquoted `&` terminates the command, but here it's used in the middle of what would otherwise be a shell word. This most commonly happens when copying a URL with query string parameters without escaping the `&`.
Either quote or escape the `&` if you wanted it as a literal ampersand, or add a space after it to make it easier to see where the previous command stopped.
### Exceptions:
If you do want to background one command and run another, e.g. `sleep 10&wait`, just add a space or linefeed after the `&` to make this more obvious: `sleep 10& wait`
This does not change the meaning of the script, it just makes it clear to ShellCheck (and other humans) that the `&` isn't supposed to be a part of the shell world.
### Related resources:
* Help by adding links to BashFAQ, StackOverflow, man pages, POSIX, etc!