Addresses review feedback on #10 regarding a TOCTOU (Time-Of-Check-Time-Of-Use) race condition in the fork/exec implementation.

Changes

• Removed access() check before execl() in stubs/FFI/sys_ffi.c

  • Eliminates race window between permission check and execution
  • execl() already fails appropriately for inaccessible files
  • Child process handles execution failures via exit status 127

• Retained path validation (absolute path requirement, no ".." sequences)

// Before: TOCTOU vulnerability
if (access(process_path, X_OK) != 0) {
  return PATH_ERROR;
}
// ... later ...
execl(process_path, process_path, NULL);

// After: Direct execution with proper error handling
execl(process_path, process_path, NULL);
// Failure handled in child: _exit(127)

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