errno (-- errnoRef)

Returns one Int32 Ref to the current thread’s error-number storage.

C runtime scope

• The module exposes one C runtime or POSIX-style error-number location.
• On Windows this accessor designates C runtime errno storage, not the separate last-error state used by many Win32 APIs.
• The page documents the error-number channel used by low-level imported functions and thin wrappers.

Read timing and overwrite

• The current value is most meaningful immediately after the relevant failing call.
• Later library or platform calls in the same thread may overwrite the stored value before it is read.
• Storing the current numeric value in a separate Int32 variable preserves it independently of later overwrites.

Thread-local behavior

• The returned reference designates the current thread’s error-number storage.
• Different threads may therefore observe different values through this interface.
• Writing through the returned Ref changes the value later reads in the same thread observe.

Examples

Linux runtime example

"linux/errno" use
"String" use
"control" use

{} Int32 {} [
  123 errno set
  errno new toString print
  LF print
  0
] "main" exportFunction

Expected Output

123

See also

• file: File I/O helpers for byte arrays and String values.
• linux/socket: Linux socket declarations, constants, address schemas, and imported functions.
• linux/posix: POSIX process, timing, descriptor, and context declarations used by Linux support modules.
• linux/Process · windows/Process: Cross-platform process wrapper with explicit creation, waiting, and termination helpers.
• windows/kernel32: Kernel32 declarations for synchronization, process, thread, file, and timing helpers.
• windows/ws2_32: Winsock2 declarations for sockets, overlapped I/O, and address-resolution helpers.