I would be useful to have more shell_command parameters. We encountered a case where 3 was too few and the solution we adopted was not too clean.
Here a recent example: An external utility script for use of external REST APIs.
Parameters: <HTTP_METHOD> <API_URL> <JSON_HEADERS> <JSON_PARAMS>
If you also must pass <JSON_PROXIES> as parameter, you'll need 5 instead of 4.
And, if the external script supports standard Unix/Linux options/params format, you'll need even more!
You might give a strong example of the usage of 5 parameters if you want the community to follow you :)
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