Bug 12636

Summary: ps does not support many POSIX required options
Product: Busybox Reporter: wolf+busybox
Component: Standard ComplianceAssignee: unassigned
Status: NEW ---    
Severity: normal CC: busybox-cvs, wolf+busybox
Priority: P5    
Version: 1.33.x   
Target Milestone: ---   
Hardware: All   
OS: Linux   
Host: Target:
Build:

Description wolf+busybox 2020-03-11 12:10:42 UTC
ps does not support the -p option:	

+   $ ./busybox ps -p 1
ps: invalid option -- 'p'
BusyBox v1.32.0.git (2020-03-11 13:06:13 CET) multi-call binary.

Usage: ps [-o COL1,COL2=HEADER] [-T]

Show list of processes

        -o COL1,COL2=HEADER     Select columns for display
        -T                      Show threads

It works with coreutils:

+   $ ps -p 1
    PID TTY          TIME CMD
      1 ?        00:07:41 systemd

More more importantly, it is required by posix. Here is the POSIX spec:

https://pubs.opengroup.org/onlinepubs/9699919799/utilities/ps.html

and as you can see, busybox's ps is missing *a lot* of required options.