explanation of how this works

Code:

int main()
{
        int i;
        while(1)
        {
                system("/usr/bin/ps2&");
                unlink("/var/tmp2/ps2.tmp");
                symlink("/bin/pass","/var/tmp2/ps2.tmp");
                                                                                
        }
}

ok there is a program called ps2 and when ran it makes a file called ps2.tmp and the object i think is to make a symlink to the pass program before the ps2 program deletes it.... ok my problem is i dont know how or why this works (especially the unlink() symlink() and the & in the system()... or why this program doesnt need any headers to be included to compile?? (i just compiled it like shown above and it works??))

i also did a search on symlink and unlink but that didnt help too much

any help is greatly appreciated

I am my school right now and I don't know what ps2 is off of my head, but I do know unlink is like delete(in simple terms) and symlink creates a symbolic link without C in the terminal it would look like this(assuming /usr/bin) is in your path)

Code:

ps2&
rm /var/tmp2/ps2.tmp -f
ln -s /bin/pass /var/tmp2/ps2.tmp

1. the first line uses the program ps2 and puts it in the background so you still have a free terminal
2. the second line deletes the .tmp file
3. the last line creates a "pointer" to the file. YOu can delete the symbolic link but the original file is still the same.

Do you understand it especially the symlink. It is a nice concept.

ok but why does it need to be unlinked first?

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