[qezem]

Fixes #347
Fixes #177

This PR updates command-line usage error messages in cmp to match GNU cmp behavior:

• Adds the executable name prefix (<executable>: ) to all usage error messages.
• Appends the <executable>: Try '<executable> --help' for more information. hint line.
• Reports specific operand and option errors (missing operand after '...', extra operand '...', unrecognized option '...', and option requires an argument -- '...') instead of a generic Usage: line.
• Updates existing unit tests and adds integration tests verifying the GNU-compatible stderr output.

[codspeed]

Merging this PR will degrade performance by 30.12%

1 warning

⚠️ 24 benchmarks are dominated by system calls

System calls cannot be simulated consistently and are left out of the measure. The reported value understates the real cost. Switch to the Walltime instrument to measure them.

Learn more about system calls

See affected benchmarks

❌ 1 regressed benchmark
✅ 25 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
❌	cmp_parser	10.6 µs	15.1 µs	-30.12%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing qezem:fix/cmp-usage-error (6c210fd) with main (a003a80)}

[qezem]

i dont know how to optimize it...