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+# ps(1)
+
+```
+ps [opt]
+  opt:
+    --no-header .... do not print column header
+    -o <OUT> ....... comma separated list of output columns
+    -p <PID> ....... only show pid
+    -C <name> ...... only show processes matching name
+    -T ............. list threads
+    --signames ..... use short signames instead bitmasks
+```
+> Set `PS_FORMAT` env variable to setup default output columns.
+
+Frequently used output columns
+```
+pid        process id
+ppid       parent process id
+pgid       process group id
+tid        thread id
+
+comm       name of process
+cmd        name of process + args (full)
+
+etime      elapsed time (since process started)
+user       user owning process
+thcount    thread count of process
+nice       nice value (-20 highest priority to 19 lowest)
+
+pcpu       cpu utilization (percent)
+pmem       physical resident set (rss) (percent)
+rss        physical memory (in kb)
+vsz        virtual memory (in kb)
+
+sig        mask of pending signals
+sigcatch   mask of caught signals
+sigignore  mask of ignored signals
+sigmask    mask of blocked signals
+```
+
+## Example: Use output for scripting
+```sh
+# Print the cpu affinity for each thread of process 31084.
+for tid in $(ps -o tid --no-header -T -p 31084); do
+    taskset -c -p $tid;
+done
+```
+
+## Example: Watch processes by name
+```sh
+watch -n1 ps -o pid,pcpu,pmem,rss,vsz,state,user,comm -C fish
+```
+
+## Example: Show signal information
+```sh
+# With signal masks.
+ps -o pid,user,sig,sigcatch,sigignore,sigmask,comm -p 66570
+
+# With signal names.
+ps --signames -o pid,user,sig,sigcatch,sigignore,sigmask,comm -p 66570
+```