LinuxQuestions.org - Is running a standalone browser in Ubuntu still limited user?

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Quote:

Originally Posted by JASlinux (Post 6495106)

You can put a standalone portable in a system folder, but they can also be most other locations.
When you put a browser out of the system, it will commonly not run with restricted permissions, logically, when it will run as root.

That is just wrong. The permissions of a process depends on the user who started, not on the location (where is it stored).
Again, all of the processes inherit permissions/rights/ownership from the parent process (where they were started from). Only root has right to modify it. The location of the binary is completely irrelevant.
The access to any file/dir depends on the current user and group (of the process, which wanted to access it), and the access rights of the given path.

Simple Example:

A stand alone executable. This will run as the user who ran the executable. Doesn't matter what directory it it in.

cpuload.c

Code:

//gcc cpuload.c -o cpuload



#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <assert.h>



static int cores = 2; //Set number of cpu cores here for cpu usage



static void cpu_load() {

    static long last_user, last_nice, last_sys;

    long user, nice, sys;

    char id[16];



    FILE * const fp = fopen( "/proc/stat", "r" );



    fscanf(fp, "%s %ld %ld %ld", id, &user, &nice, &sys);

    fclose(fp);



    char *percent = malloc(256);

    int per;

    sprintf(percent, "%ld\n", 

        (user + nice + sys) - (last_user + last_nice + last_sys));

    sscanf(percent, "%d", &per);

    printf("%s%d\n", "Percent CPU Usage : ", per / cores);



    last_user = user;

    last_nice = nice;

    last_sys = sys;

}



int main(void)

{

    assert( sysconf(_SC_CLK_TCK) == 100 );

    for(;;) {

        cpu_load();

        sleep(1);

        printf("\033[2J\033[1;1H");

    }

}

Run that executable. Then in another shell:

Code:

ps a -o pid,tty,etime,cmd,user