- /* Check for existence of required macros. Note that we document
- that these are safe only on lvalues. */
- int i;
- for (i = 0; i < 0x10000; i = (i ? i << 1 : 1))
- {
- /* POSIX requires that for all valid process statuses, that
- exactly one of these three macros is true. But not all
- possible 16-bit values map to valid process status.
- Traditionally, 8 of the bits are for WIFEXITED, 7 of the bits
- to tell between WIFSIGNALED and WIFSTOPPED, and either 0x80
- or 0x8000 to flag that core was also dumped. Since we don't
- know which byte is WIFEXITED, we skip the both possible bits
- that can signal core dump. */
- if (i == 0x80)
- continue;
- if (!!WIFSIGNALED (i) + !!WIFEXITED (i) + !!WIFSTOPPED (i) != 1)
- return 1;
- }
- i = WEXITSTATUS (i) + WSTOPSIG (i) + WTERMSIG (i);