Accessing a process command line without ps

I work on embedded boards quite a lot, and often the ps command utility is a bare bones busybox stripped down version without options. One of the issues I faced while using it is that it truncates the process command line, and options that would allow it to display an untruncated output are not available.

I remembered that every active process has it’s entry in /proc/<PID>/cmdline and i tried to use it directly. Unfortunately the output of /proc/<PID>/cmdline contains the individual arguments separated by null characters(\000). The \000 character is printed as a @ in my terminal which is unusable to copy/paste. I also did not have a hexadecimal dumper to know what exactly was the character. Fortunately stackoverflow came to the rescue:

cat /proc/$PID/cmdline | tr '\000' ' ' # The solution i would come to
cat /proc/$PID/cmdline | xargs -0 echo # xargs showing it's versatility.

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