查看一个进程有多少个线程

# pwd
/proc/68
# cat status
Name:    nfsiod
State:    S (sleeping)
Tgid:    68
Ngid:    0
Pid:    68
PPid:    2
TracerPid:    0
Uid:    0    0    0    0
Gid:    0    0    0    0
FDSize:    64
Groups:    
Threads:    1
SigQ:    0/965
SigPnd:    0000000000000000
ShdPnd:    0000000000000000
SigBlk:    0000000000000000
SigIgn:    ffffffffffffffff
SigCgt:    0000000000000000
CapInh:    0000000000000000
CapPrm:    0000003fffffffff
CapEff:    0000003fffffffff
CapBnd:    0000003fffffffff
CapAmb:    0000000000000000
Cpus_allowed:    f
Cpus_allowed_list:    0-3
voluntary_ctxt_switches:    2
nonvoluntary_ctxt_switches:    0

 cat /proc/652/status | grep Threads