Displaying /proc/PID/cmdline with space
On linux, the file /proc/PID/cmdline shows the command line for the process. If you check content of this file, you will see the command, but arguments are not seperated by space.
To display the command line with space, run
cat /proc/PID/cmdline | tr '\000' ' '
Or
cat /proc/PID/cmdline | xargs -0 echo
Example
To display environ file, run
cat environ | xargs -0 -L1 echo