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From: Jasen Betts <jasen@xnet.co.nz>
Newsgroups: comp.os.linux.development.apps
Subject: Re: How does one use capabilities
Date: 12 Feb 2014 09:41:38 GMT
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On 2014-02-12, Andrew Falanga <af300wsm@gmail.com> wrote:
> Hi,
>
> I'm learning about something that I didn't even know was in Linux for quite some time now: capabilities.  How do they actually get set?
>
> I did something like this:

ignoring for now the memory leak.


>
> #include <iostream>
> #include <sys/types.h>
> #include <unistd.h>
> #include <sys/capabilities.h>

shoule be 
#include <sys/capability.h>

>
> int main() {
>     cap_t caps = cap_get_pid(getpid());
>
>     std::cout << "capabilities: " << cap_to_text(caps) << std::endl;

should be 
  cap_to_text(caps,NULL) 
  
,which leaks memory, but atleast doesn't give undefined behaviour.

>     return 0;
> }
>

> Which returns "=".  It seems unlikely that the process has no capabilities.  Plus, every code example I've found thus far (which isn't many) shows that one first allocates a cap_t struct with cap_init() and then sets the values he wishes and then calls cap_set_pid() or similar.  Is this how it's supposed to be used?

well, in spite of all that it seems to be working.
try running it as root.

-- 
Neither the pheasant plucker, nor the pheasant plucker's son.


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