how dangerous is this

[Journer]

so i am taking my first c++ under unix class and i'm wondering what would happen if you ran this code:

#include <iostream>
#include <string>
using namespace std;
int main(){
string str;
int pid = fork();
int a=0;
while(pid!=0){
pid=fork();
str="g++ bigapp.ccp -o ";
char c=a;
str.insert(18,c);
system(str);
a++;
}
return 0;}

from the way i understand it, the code would keep creating new processes that compile the bigapp.ccp with a new name each time. if the application took a considerable amount of time to compile wouldnt this program eventually crash the PC because it would be running so many times and trying to compile each time. essentially it would try to do this forever right? since the pid will never be 0 again. or am i wrong?

i would have run it on the server we do our programming on but i was scared >.>

 

[aCynic2]

You'd use up all PID and/or mem and PO a lot of people.

 

[Journer]

Originally posted by: aCynic2
You'd use up all PID and/or mem and PO a lot of people.

and eventually brining the system down or slowing it down a ton, no?

 

[CTho9305]

Most modern unix OSes have per-user process limits. If your system is properly configured, everyone else will be slightly annoyed, and you'll have to find a way to forcefully log yourself out / kill your processes.

edit: By the way, that's called a "fork bomb".

 

[Journer]

Originally posted by: CTho9305
Most modern unix OSes have per-user process limits. If your system is properly configured, everyone else will be slightly annoyed, and you'll have to find a way to forcefully log yourself out / kill your processes.

awww....i thought i was a l557 hax0r >_<!!!

 

[imported_LoKe]

Just write a simple loop. It'll slowly but surely bog down a system.

$int = 1
while($int != 0){
$int++;
print "Have a nice day";
}

Or...

int i;
i = 1;
while(i != 0){
i++;
}

 

[CTho9305]

Originally posted by: LoKe
Just write a simple loop. It'll slowly but surely bog down a system.

$int = 1
while($int != 0){
$int++;
print "Have a nice day";
}

Or...

int i;
i = 1;
while(i != 0){
i++;
}

Neither of those will do much unless you're on a single-CPU / single-core machine and your processes run at a higher priority than everybody else's. Those two loops are no different from running one instance of one of seti@home, folding@home, prime95, etc.

 

[Aikouka]

Wouldn't you also run into invalid characters eventually? Also, you're starting at 'a', which is a poor choice. 'A' is character 65 and 'a' is character 97, therefore you're skipping the entire uppercase section and even numbers. I don't really tinker with linux enough to know its restrictions on file names.

http://www.asciitable.com/ for a reference.

 

[imported_LoKe]

Originally posted by: CTho9305
Neither of those will do much unless you're on a single-CPU / single-core machine and your processes run at a higher priority than everybody else's. Those two loops are no different from running one instance of one of seti@home, folding@home, prime95, etc.

Run the script multiple times.

 

[CTho9305]

Originally posted by: LoKe

Originally posted by: CTho9305
Neither of those will do much unless you're on a single-CPU / single-core machine and your processes run at a higher priority than everybody else's. Those two loops are no different from running one instance of one of seti@home, folding@home, prime95, etc.

Run the script multiple times.

I suspect you haven't actually tried this.

 

[imported_LoKe]

Originally posted by: CTho9305

Originally posted by: LoKe

Originally posted by: CTho9305
Neither of those will do much unless you're on a single-CPU / single-core machine and your processes run at a higher priority than everybody else's. Those two loops are no different from running one instance of one of seti@home, folding@home, prime95, etc.

Run the script multiple times.

I suspect you haven't actually tried this.

I live in constant fear.

 

[Nothinman]

http://en.wikipedia.org/wiki/Fork_bomb

Why waste your time compiling a fork bomb when you can just use the shell?

 

[tfinch2]

Originally posted by: Nothinman
http://en.wikipedia.org/wiki/Fork_bomb

Why waste your time compiling a fork bomb when you can just use the shell?

<borat> NICE! </borat>

 

[irishScott]

OK, so apparently FuseTalk can't handle code indentation, spacing, or "return"s :roll: Withdrawn.

 

[Journer]

Originally posted by: irishScott
OK, so apparently FuseTalk can't handle code indentation, spacing, or "return"s :roll: Withdrawn.

eh?

 

[Nothinman]

OK, so apparently FuseTalk can't handle code indentation, spacing, or "return"s Withdrawn.

Not unless you use the attach code button.

 

[Red Squirrel]

I remember back in first year college we did our programming off a citrix server.

They realized how bad of an idea that was, the year after we had our own private programming lab that was off the main network. At least once a day we'd have to get IT to shut down a process or even reboot one of the servers. This was vB at the time, so thats slow on its own. a simple increment loop written in vB will pretty much bog down the server. Funny thing is, most of the time it was not intentional.

 

[Journer]

haha...its been three weeks of this class an so far i've learned how to DOS a system and spam the world from a fake email...mwuahahaha i :heart: c++