Overview

By changing the argv[0] variable (language specific), we can change the visible name of a process.

Details

The program:

#include <unistd.h>
#include <string.h>
#include <stdio.h>

int main(int argc, char *argv[]) {

    printf("pid: %i\n", getpid());

    char psname[] = "systemd";
    strncpy(argv[0],psname,strlen(argv[0]));

    sleep(300);

    return 0;
}

Compile:

gcc ./myOriginalProgramName.c -o myOriginalProgramName

Execute with the name ./myOriginalProgramName:

jemurray@home-server:~/processname$ ./myOriginalProgramName
pid: 31514

Examine the current process table, the name has been changed from myOriginalProgramName to systemd:

jemurray@home-server:~$ ps -ef | grep 31514
jemurray 31514 29114  0 13:12 pts/8    00:00:00 systemd