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-o format user-defined format.
format is a single argument in the form of a blank-separated or comma-separated list, which offers a
way to specify individual output columns. The recognized keywords are described in the STANDARD FORMAT
SPECIFIERS section below. Headers may be renamed (ps -o pid,ruser=RealUser -o comm=Command) as
desired. If all column headers are empty (ps -o pid= -o comm=) then the header line will not be
output. Column width will increase as needed for wide headers; this may be used to widen up columns
such as WCHAN (ps -o pid,wchan=WIDE-WCHAN-COLUMN -o comm). Explicit width control
(ps opid,wchan:42,cmd) is offered too. The behavior of ps -o pid=X,comm=Y varies with personality;
output may be one column named "X,comm=Y" or two columns named "X" and "Y". Use multiple -o options
when in doubt. Use the PS_FORMAT environment variable to specify a default as desired; DefSysV and
DefBSD are macros that may be used to choose the default UNIX or BSD columns.
Então tente:
/bin/ps -o uname:1,ppid:1,pid:1