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19 lines
767 B
Markdown
19 lines
767 B
Markdown
# Check If Command Is Executable Before Using
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When writing a quick bash script, you may want to check if a command exists and
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is executable before trying to call it. This can be done with `command`, a builtin shell command, and the `-v` flag.
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> If the -V or -v option is supplied, the exit status is 0 if command was found, and 1 if not.
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Knowing that, we can redirect the output of the command to `/dev/null` and then
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short-circuit executing the command if it's not available.
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```bash
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command -v pbcopy >/dev/null 2>&1 && echo 'something' | pbcopy
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```
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In this example, I execute the `pbcopy` command, which copies text to my system
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clipboard, only if that command is available and executable.
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See `man bash` and find the listing for `command` for more details.
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