HFILEERROR

HFILEERROR is a sentinel value used in legacy file I/O APIs that operate on an HFILE handle. It signals that a function attempting to return an HFILE has failed. In most documentation and code, this value is defined as an invalid handle, typically represented as -1, and cast to the HFILE type.

In the OS/2 and DOS high-level file I/O libraries, many operations such as opening, reading, writing, or closing a file return an HFILE on success or HFILE_ERROR on failure. A returned HFILE_ERROR indicates that the operation did not complete, and the programmer should handle the error according to the platform’s error reporting conventions. The exact cause of the failure is usually obtained through the system’s error reporting mechanism associated with the API, referenced by the function’s documentation.

HFILE handles and the HFILE_ERROR sentinel are part of legacy 16-bit and early 32-bit environments. They were common in the OS/2, DOS, and early Windows-era high-level file I/O libraries. Modern software development on Windows generally uses the Win32 API with HANDLEs or standard C FILE streams, where different error reporting schemes apply. As a result, HFILE and HFILE_ERROR are largely of historical interest and are rarely used in contemporary code, except when maintaining or interfacing with older applications or legacy systems.