_outp, _outpw, _outpd
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_outp, _outpw, _outpd

Output a byte(_outp), a word(_outpw), or a double word (_outpd) at a port.

int _outp(
   unsigned short port,
   int databyte 
unsigned short _outpw(
   unsigned short port,
   unsigned short dataword 
unsigned long _outpd(
   unsigned short port,
   unsigned long dataword 


Port number.
databyte, dataword
Output values.

Return Value

The functions return the data output. There is no error return.


The _outp, _outpw, and _outpd functions write a byte, a word, and a double word, respectively, to the specified output port. The port argument can be any unsigned integer in the range 0 – 65,535; databyte can be any integer in the range 0 – 255; and dataword can be any value in the range of an integer, an unsigned short integer, and an unsigned long integer, respectively.


Routine Required header Compatibility
_outp <conio.h> Win 95
_outpw <conio.h> Win 95
_outpd <conio.h> Win 95

For additional compatibility information, see Compatibility in the Introduction.


All versions of the C run-time libraries.

See Also

Console and Port I/O Routines | _inp | Run-Time Routines and .NET Framework Equivalents

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