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Closes a file.


int _close(   
   int fd   


File descriptor referring to the open file.

Return Value

_close returns 0 if the file was successfully closed. A return value of –1 indicates an error.


The _close function closes the file associated with fd.

The file descriptor and the underlying OS file handle are closed. Thus, it is not necessary to call CloseHandle if the file was originally opened using the Win32 function CreateFile and converted to a file descriptor using _open_osfhandle.

This function validates its parameters. If fd is a bad file descriptor, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, the functions returns -1 and errno is set to EBADF.


Routine Required header Optional header
_close <io.h> <errno.h>

For more compatibility information, see Compatibility in the Introduction.


See the example for _open.

See Also

Low-Level I/O
_creat, _wcreat
_dup, _dup2
_open, _wopen
_unlink, _wunlink