Use "procstat" to get process info

On FreeBSD, you can use procstat command to get detailed info of process. E.g.:

# procstat 521
PID  PPID  PGID   SID  TSID THR LOGIN    WCHAN     EMUL          COMM
521     1   521   521     0   1 root     select    FreeBSD ELF64 syslogd

The above outputs describe the info of process whose PID is 521: its PID, parent PID, command name, etc.

If you want to display all processes' info, use -a option:

# procstat -a
PID  PPID  PGID   SID  TSID THR LOGIN    WCHAN     EMUL          COMM
0     0     0     0     0  10 -        -         -             kernel
1     0     1     1     0   1 root     wait      FreeBSD ELF64 init
2     0     0     0     0   2 -        -         -             cam
3     0     0     0     0   1 -        idle      -             mpt_recovery0
4     0     0     0     0   1 -        waiting_  -             sctp_iterator
5     0     0     0     0   2 -        umarcl    -             pagedaemon
6     0     0     0     0   1 -        psleep    -             vmdaemon
7     0     0     0     0   1 -        pgzero    -             pagezero

There are many options you can use for procstat, i.e., if you are curious about thread info, use -t option:

# procstat -t 521
PID    TID COMM             TDNAME           CPU  PRI STATE   WCHAN
521 100065 syslogd          -                  0  120 sleep   select

For details of every option, please refer the manual.