To get the command line of a process without the ps command, and the PID of the command is known, use this command. This example is using a process with a PID of 28633.
ubuntu ~ $ cat /proc/28633/cmdline ; echo upstart-socket-bridge--daemon |
This will show the command line of the process without using the ps command. So blocking the ps command on a Linux system will not stop users from gaining information about the command-line switches used by a certain process.
This is another example. Not all processes in the /proc directory have a cmdline entry, but it is very useful when you find one.
ubuntu ~ $ cat /proc/1771/cmdline ; echo /sbin/getty-838400tty1 |
Of course, if the ps command is really required, then get the command line like this.
ubuntu ~ $ ps -ww 1771 PID TTY STAT TIME COMMAND 1771 tty1 Ss+ 0:00 /sbin/getty -8 38400 tty1 |
This is a better example, this gets the command line of the Systemd process.
jason@jason-Lenovo-H50-55:~$ cat /proc/$(pidof systemd)/cmdline ; echo /lib/systemd/systemd--user |
Another example. This is quite easy to do.