Here you are allocating memory

char* str1 =(char *) malloc(80*sizeof(char));

but this memory has not been initialized to zero by malloc

The following may or may not fail because the...

I am confused. First you say you want to write the program. Then you say you want somebody to send the code for such a program to you.

Here is a java applet. http://media.pearsoncmg.com/aw/aw_kurose_network_2/applets/csmacd/csmacd.html

The problem is with the line

path = "ragHu";


It should be replaced with the following

strcpy(path, "ragHu");

You can use the strip utility to remove all the symbols from your object file.

Alternatively, declare sayHello() to be a static function.

What type of programs are you talking about? Give an example of what you want to do.

Sounds like homework. Show us what you have done so far and prehaps somebody here might help you.