Qiita Teams that are logged in
You are not logged in to any team

Log in to Qiita Team
OrganizationEventAdvent CalendarQiitadon (β)
Qiita JobsQiita ZineQiita Blog
Help us understand the problem. What are the problem?

More than 3 years have passed since last update.

posted at

time, touch, tree コマンド

この記事は Linux コマンド 全部オレ Advent Calendar 2017 の15日目の記事です。


       time - time a simple command or give resource usage

       time [options] command [arguments...]

       The  time  command runs the specified program command with the given arguments.  When command finishes, time writes a message to
       standard error giving timing statistics about this program run.  These statistics consist of (i) the elapsed real  time  between
       invocation  and  termination, (ii) the user CPU time (the sum of the tms_utime and tms_cutime values in a struct tms as returned
       by times(2)), and (iii) the system CPU time (the sum of the tms_stime and tms_cstime values in  a  struct  tms  as  returned  by

       Note: some shells (e.g., bash(1)) have a built-in time command that provides less functionality than the command described here.
       To access the real command, you may need to specify its pathname (something like /usr/bin/time).


real, user, sys

[sinsengumi ~]$ time sleep 4
real    0m4.002s
user    0m0.001s
sys     0m0.000s
用語 英語 意味
real real time プログラムの呼び出しから終了までにかかった実時間
user user CPU time プログラムが CPU を使った時間(プログラム自身の処理時間)
sys system CPU time プログラム以外(OS)が CPU を使った時間(プログラムに伴って OS が仕事をした時間)


       touch - change file timestamps

       touch [OPTION]... FILE...

       Update the access and modification times of each FILE to the current time.

       A FILE argument that does not exist is created empty, unless -c or -h is supplied.

       A  FILE argument string of - is handled specially and causes touch to change the times of the file associated with standard out‐



[sinsengumi ~]$ ls -l
total 0
[sinsengumi ~]$ touch a.txt
[sinsengumi ~]$ ls -l
total 0
-rw-r--r-- 1 sinsengumi sinsengumi 0 Dec 15 16:36 a.txt
[sinsengumi ~]$ touch a.txt
[sinsengumi ~]$ ls -l
total 0
-rw-r--r-- 1 sinsengumi sinsengumi 0 Dec 15 16:37 a.txt


       tree - list contents of directories in a tree-like format.

       tree  [-acdfghilnpqrstuvxACDFQNSUX] [-L level [-R]] [-H baseHREF] [-T title] [-o filename] [--nolinks] [-P pattern] [-I pattern]
       [--inodes] [--device] [--noreport] [--dirsfirst] [--version] [--help] [--filelimit #] [--si] [--prune] [--du] [--timefmt format]
       [directory ...]

       Tree  is a recursive directory listing program that produces a depth indented listing of files, which is colorized ala dircolors
       if the LS_COLORS environment variable is set and output is to tty.  With no arguments, tree  lists  the  files  in  the  current
       directory.   When directory arguments are given, tree lists all the files and/or directories found in the given directories each
       in turn.  Upon completion of listing all files/directories found, tree returns the total  number  of  files  and/or  directories

       By default, when a symbolic link is encountered, the path that the symbolic link refers to is printed after the name of the link
       in the format:

           name -> real-path

       If the `-l' option is given and the symbolic link refers to an actual directory, then tree will follow the path of the  symbolic
       link as if it were a real directory.



[sinsengumi nginx]$ tree
├── conf.d
│   ├── default.conf
│   └── reverse_proxy.conf
├── fastcgi_params
├── koi-utf
├── koi-win
├── mime.types
├── modules -> ../../usr/lib64/nginx/modules
├── nginx.conf
├── scgi_params
├── uwsgi_params
└── win-utf
Why not register and get more from Qiita?
  1. We will deliver articles that match you
    By following users and tags, you can catch up information on technical fields that you are interested in as a whole
  2. you can read useful information later efficiently
    By "stocking" the articles you like, you can search right away
Help us understand the problem. What are the problem?