How do you direct info to a port using C programming language?

first of all, all of this is for someone on a unix system. you first need a couple of system includes:


#include %26lt;sys/types.h%26gt;


#include %26lt;sys/socket.h%26gt;


#include %26lt;netinet/in.h%26gt;





then you need to use the socket() system call to open a socket; and then bind() to bind the socket to a port number. then you listen() for a connection and accept() it. and then write() your data. these are all system calls which you should be able to read up on using man.





there's a bit more to it, but you can read about it all in greater detail at the link below.

How do you direct info to a port using C programming language?
Please be careful while doing this, as it may damage some peripheral of your computer. Please visit wwww.learn-c.com for details.





Here is a sample code:





// digi3c.c





// The following are known only to the functions in this file.


// They can't be modified or even accessed by anything outside this


// file except through funtions in this file designed to provide access.


unsigned base;


unsigned switch_port;


unsigned ppi_porta;


unsigned ppi_portb;


unsigned ppi_portc;





int porta_val;


int porta_mask;





int portb_val;


int portb_mask;





int portc_val;


int portc_mask;








// ========================================...


// is_closure


// 1. Return -1 error indicator if the input


// is less than 1 or greater than 67.


//


// 2. If there is a fall-through from the above and the input


// is less than 4, return the status based on switch_port.


//


// 3. If there is a fall-through from both of the above, then


// return the status based on the matrix:





// |-----------------------|


// Port A bit 0| 4| 5| 6| 7| 8| 9|10|11|


// Port A bit 1|12|13|14|15|16|17|18|19|


// Port A bit 2|20|21|22|23|24|25|26|27|


// Port A bit 3|28|29|30|31|32|33|34|35|


// Port A bit 4|36|37|38|39|40|41|42|43|


// Port A bit 5|44|45|46|47|48|49|50|51|


// Port A bit 6|52|53|54|55|56|57|58|59|


// Port A bit 7|60|61|62|63|64|65|66|67|


// |-----------------------|


// Port B bits 0 1 2 3 4 5 6 7





// ========================================...


int is_closure(int input)


{





if(input %26lt; 1 || input %26gt; 67) // if the input is less than 1 or greater


return -1; // than 67, then return -1 showing an error





// we fell through the above so see if input is less than 4


if(input %26lt; 4)


return ((inp(switch_port) %26gt;%26gt; (input + 3)) %26amp; 1) ^ 1; // yes, return using switch_port





// input is %26gt;= 4 so look at the matrix


// by first setting up Port A to take the appropriate row bit low


porta_val = (~(1 %26lt;%26lt; ( (input - 4) / 8) )) %26amp; 0xff;





// clear the appropriate Port A bit


outp(ppi_porta, porta_val);





// determine what column bit to look at for this input


portb_mask = (1 %26lt;%26lt; ((input - 4) % 8)) %26amp; 0xff;





// a closure will cause a low, so invert the return


if(!(inp(ppi_portb) %26amp; portb_mask))


return 1;





return 0;





}// end is_closure()








// set up the ppi according to the dictates of the mode argument


void set_up_ppi(int mode)


{


unsigned control = base + 0x23;


int command;





command = (mode %26amp; 0x0c) %26lt;%26lt; 1; // shift bits 2 and 3 into positions 3 and 4


command += (mode %26amp; 3); // add in bits 0 and 1


command |= 0x80; // OR in bit 7 for PPI set up





outp(control, command); // set according to mode command





} // end set_up_ppi()








// get the port -- this will grow into an auto-detect function in the future


void get_port(void)


{


base = 0x300;


switch_port = base + 0x18;


ppi_porta = base + 0x20;


ppi_portb = base + 0x21;


ppi_portc = base + 0x22;





} // end get_port()