eof.cpp File Reference

#include <corecrt_internal_lowio.h>

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Functions
int __cdecl	_eof (int const fh)

Function Documentation

_eof()

int __cdecl _eof

(

int const

fh

)

Definition at line 16 of file eof.cpp.

{
    _CHECK_FH_CLEAR_OSSERR_RETURN(fh, EBADF, -1);
    _VALIDATE_CLEAR_OSSERR_RETURN((fh >= 0 && (unsigned)fh < (unsigned)_nhandle), EBADF, -1);
    _VALIDATE_CLEAR_OSSERR_RETURN((_osfile(fh) & FOPEN), EBADF, -1);
 
    return __acrt_lowio_lock_fh_and_call(fh, [&]()
    {
        if ((_osfile(fh) & FOPEN) == 0)
        {
            errno = EBADF;
            _doserrno = 0;
            _ASSERTE(("Invalid file descriptor. File possibly closed by a different thread",0));
            return -1;
        }
 
        __int64 const here = _lseeki64_nolock(fh, 0ll, SEEK_CUR);
        if (here == -1ll)
            return -1;
 
 
        __int64 const end = _lseeki64_nolock(fh, 0ll, SEEK_END);
        if (end == -1ll)
            return -1;
 
        // Now we can test if we're at the end:
        if (here == end)
            return 1;
 
        // If we aren't at the end, we need to reset the stream to its original
        // state before we return:
        _lseeki64_nolock(fh, here, SEEK_SET);
        return 0;
    });
}