CYGPKG_LIBC_ERRNO
Dummy
This package controls the behavior of the errno variable (or more strictly, expression) from errno.h.
CYGSEM_LIBC_PER_THREAD_ERRNO
Boolean
This option controls whether the standard error code reporting variable errno is a per-thread variable, rather than global. Enabling this option will use one slot of kernel per-thread data. You should ensure you have enough slots configured for all your per-thread data.
CYGNUM_LIBC_ERRNO_TRACE_LEVEL
Count
Trace verbosity level for debugging the errno retrieval mechanism in errno.cxx. Increase this value to get additional trace output.