get _complete_ process name from pid

Question

I am in a kernel module and I want to have the whole process name from a given pid. exactly: I want the line which is hold in /proc/PID/cmdline. The problem is that `task_struct->comm[]` is only 15 bytes long and doesn't handle if a program changes his `argv[]` manually or via setproctitle(3)... Any ideas? :)

Accepted Answer

You could always look at how the kernel does it. You'll see the function:

```
proc_pid_cmdline(struct task_struct *task, char * buffer)
```

It's fairly easy to follow but once you have the `task_struct` for the process you are interested in you use `access_process_vm()` to slurp the bits you want from `mm->arg_start`.

get _complete_ process name from pid

Solution

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