Re: [Mingw-users] Help - where is the C language sleep() function?

[Brian D. <br...@de...>]

Roger Wells wrote:

> not so fast.
> when I am using MinGW with gcc 3.3.1 code using sleep() compiles, links
> and runs as expected
> on the other hand using MinGW gcc 3.4.5, code using sleep() reports it
> as an unresolved reference at link time.
> replacing sleep with _sleep in the source files fixes this.
> 
> versions:
> gcc version 3.3.1 (mingw special 20030804-1)
> GNU ld version 2.13.90 20030111
> and
> gcc version 3.4.5 (mingw special)
> GNU ld version 2.17.50 20060716
> 
> Also sleep is a common function but not completely standard (no mention
> of it in ISO/IEC 9899 "C" spec).  It is, however, included in the POSIX
> standard.  In any case it is dangerous since on Win32 the argument is
> milliseconds and on POSIX implementations (e.g., RHEL 4.0) the units are
> seconds.

You can do that, but you're using an undocumented, obsolete, and
deprecated interface that could disappear in future revisions of
MSVCRT.  This is not a good idea in terms of general programming
practice.

/*
 * NOTE: Officially the three following functions are obsolete. The
Win32 API
 *       functions SetErrorMode, Beep and Sleep are their replacements.
 */
_CRTIMP void __cdecl    _beep (unsigned int, unsigned int)
__MINGW_ATTRIB_DEPRECATED;
/* Not to be confused with  _set_error_mode (int).  */
_CRTIMP void __cdecl    _seterrormode (int) __MINGW_ATTRIB_DEPRECATED;
_CRTIMP void __cdecl    _sleep (unsigned long)
__MINGW_ATTRIB_DEPRECATED;

_CRTIMP void __cdecl    _exit   (int) __MINGW_ATTRIB_NORETURN;

Brian