Even with SIP disabled, test_syscall currently fails on macOS due to incorrect parsing of dtruss output and Python interpretation issues (type mismatches). While one option is always to skip this test on macOS and mark it as Linux-only, the test already includes significant code and logic specifically for macOS. Therefore, fixing the existing error (and improving code coverage in the process) seems simpler than removing the macOS-specific code.

Worth noting that CI did not detect these issues because the WT Evergreen configuration does not include test_syscall on macOS. So another part of this ticket is to enable running test_syscall in the macOS CI.

Steps to reproduce:

• Use a macOS-based system
• Disable SIP
• Build WT
• Run ctest -R test_syscall

Fix proposal: 

• Fix this test on macOS
• Enable CI testing for this configuration

Definition of done:

• Test passes on macOS and this configuration covered by CI