posix: getopt: implement standards-compliant reset

[cfriedt]

Describe the bug The getopt() utility is able to restart option parsing when the caller sets optind = 1 prior to making the function call.

This does not work today in Zephyr due to what appears to be a workaround for lack of TLS emulation support.

Please also mention any information which could help others to understand the problem you're facing:

• What target platform are you using? any
• What have you tried to diagnose or workaround this issue? See also #52699 . Additionally, it may be possible to use POSIX TLS, but that excludes getopt() users who do not want to commit to pulling in all of pthread. There is a workaround which is to call getopt_init() prior to calling getopt(), but it is non-standard / non-portable, and will not work in some builds.
• Is this a regression? If yes, have you been able to "git bisect" it to a specific commit? No, technically it's been a shortcoming since it was introduced.
• ...

To Reproduce Steps to reproduce the behavior:

1. compile the sample application from #52699 and then try to run something similar as a test in Zephyr
2. See error

Expected behavior Calls to getopt() should be able to restart option parsing when optind is set to 1.

Impact It's an annoyance, but one that should be solved in a generic way, preferably with TLS.

Logs and console output

Environment (please complete the following information):

• OS: (e.g. Linux, MacOS, Windows) Any
• Toolchain (e.g Zephyr SDK, ...): Zephyr SDK 0.15.2
• Commit SHA or Version used: 0a30f41a1c8753463ea721130bee956f82743af9

Additional context Should be solvable by TLS emulation. See #52699

[cfriedt]

depends on #52699

[github-actions[bot]]

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[github-actions[bot]]

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[github-actions[bot]]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.

[github-actions[bot]]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.

[github-actions[bot]]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.

[github-actions[bot]]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.

[github-actions[bot]]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.

[github-actions[bot]]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.