Format
#include <conio.h> /* also in <builtin.h> */ int _outp( const unsigned int port, const int value );
Language Level: Extension
_outp writes a byte value to the specified port.
The port number must be an unsigned integer value
within the range 0 to 65 535 inclusive. The byte value
must be within the range 0 to 255 inclusive.
Note: _outp is a built-in function, which means it is implemented as an inline instruction and has no backing code in the library. For this reason:
You can run code containing this function only at ring zero. Otherwise, an invalid instruction exception is generated.
Return Value
_outp returns the integer value that was
output to the specified port. There is no error return value, and _outp
does not set errno.
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_inp -- Read Byte from Input
Port
_inpw -- Read
Unsigned Short from Input Port
_inpd -- Read
Doubleword from Input Port
_outpw -- Write
Word to Output Port
_outpd -- Write
Double Word to Output Port
<builtin.h>
<conio.h>