bash-basic

lvtest@auto-inst:~/tmp$ cd /usr/bin
lvtest@auto-inst:/usr/bin$ pwd
/usr/bin

lvtest@auto-inst:/usr$ pwd
/usr
lvtest@auto-inst:/usr$ cd ./bin
lvtest@auto-inst:/usr/bin$ pwd
/usr/bin

lvtest@auto-inst:/usr/bin$ pwd
/usr/bin
lvtest@auto-inst:/usr/bin$ cd
lvtest@auto-inst:~$ pwd
/home/lvtest
lvtest@auto-inst:~$ cd -
/usr/bin
lvtest@auto-inst:/usr/bin$ pwd
/usr/bin
lvtest@auto-inst:/usr/bin$ cd ~lvtest
lvtest@auto-inst:~$ pwd
/home/lvtest

lvtest@auto-inst:~$ ls -l
total 16
-rwx------ 1 lvtest lvtest  802 Oct 24 15:05 authorized_keys
drwx------ 2 lvtest lvtest 4096 Oct 24 15:05 backupssh
drwxrwxr-x 3 lvtest lvtest 4096 Oct 24 16:45 test
drwxrwxr-x 3 lvtest lvtest 4096 Feb 21 16:33 tmp
lvtest@auto-inst:~$ ls -lt
total 16
drwxrwxr-x 3 lvtest lvtest 4096 Feb 21 16:33 tmp
drwxrwxr-x 3 lvtest lvtest 4096 Oct 24 16:45 test
-rwx------ 1 lvtest lvtest  802 Oct 24 15:05 authorized_keys
drwx------ 2 lvtest lvtest 4096 Oct 24 15:05 backupssh
lvtest@auto-inst:~$ ls -lt --reverse
total 16
drwx------ 2 lvtest lvtest 4096 Oct 24 15:05 backupssh
-rwx------ 1 lvtest lvtest  802 Oct 24 15:05 authorized_keys
drwxrwxr-x 3 lvtest lvtest 4096 Oct 24 16:45 test
drwxrwxr-x 3 lvtest lvtest 4096 Feb 21 16:33 tmp

lvtest@auto-inst:~/tmp$ ls -l
total 24
-rwxrwxr-x  1 lvtest lvtest 8522 Feb 21 16:33 a.out
-rw-rw-r--  1 lvtest lvtest  222 Feb 21 16:33 printf.c
-rw-rw-r--  1 lvtest lvtest 1042 Feb 19 18:09 testsig.c
drwxrwxr-x 40 lvtest lvtest 4096 Feb 20 16:48 unpbook

lrwxrwxrwx  1 root root    17 Feb 20  2013 libip4tc.so.0 -> libip4tc.so.0.0.0

lvtest@auto-inst:~/tmp/ttt/hs$ ls
f1
lvtest@auto-inst:~/tmp/ttt/hs$ ln f1 hard-link
lvtest@auto-inst:~/tmp/ttt/hs$ ls
f1  hard-link
lvtest@auto-inst:~/tmp/ttt/hs$ ls -al
total 8
drwxrwxr-x 2 lvtest lvtest 4096 Feb 27 18:58 .
drwxrwxr-x 6 lvtest lvtest 4096 Feb 27 18:58 ..
-rw-rw-r-- 2 lvtest lvtest    0 Feb 27 18:58 f1
-rw-rw-r-- 2 lvtest lvtest    0 Feb 27 18:58 hard-link

lvtest@auto-inst:~/tmp/ttt/hs$ ls
f1  hard-link
lvtest@auto-inst:~/tmp/ttt/hs$ ln -s f1 soft-link
lvtest@auto-inst:~/tmp/ttt/hs$ ls -al
total 8
drwxrwxr-x 2 lvtest lvtest 4096 Feb 27 19:03 .
drwxrwxr-x 6 lvtest lvtest 4096 Feb 27 18:58 ..
-rw-rw-r-- 2 lvtest lvtest    0 Feb 27 18:58 f1
-rw-rw-r-- 2 lvtest lvtest    0 Feb 27 18:58 hard-link
lrwxrwxrwx 1 lvtest lvtest    2 Feb 27 19:03 soft-link -> f1

lvtest@auto-inst:~$ type type
type is a shell builtin
lvtest@auto-inst:~$ type ls
ls is aliased to `ls --color=auto'
lvtest@auto-inst:~$ type cp
cp is /bin/cp

lvtest@auto-inst:~$ which ls
/bin/ls
lvtest@auto-inst:~$ which cd

lvtest@auto-inst:~$ help cd
cd: cd [-L|[-P [-e]]] [dir]
    Change the shell working directory.

    Change the current directory to DIR.  The default DIR is the value of the
    HOME shell variable.

    The variable CDPATH defines the search path for the directory containing
    DIR.  Alternative directory names in CDPATH are separated by a colon (:).
    A null directory name is the same as the current directory.  If DIR begins
    with a slash (/), then CDPATH is not used.

    If the directory is not found, and the shell option `cdable_vars' is set,
    the word is assumed to be  a variable name.  If that variable has a value,
    its value is used for DIR.

    Options:
        -L  force symbolic links to be followed
        -P  use the physical directory structure without following symbolic
        links
        -e  if the -P option is supplied, and the current working directory
        cannot be determined successfully, exit with a non-zero status

    The default is to follow symbolic links, as if `-L' were specified.

    Exit Status:
    Returns 0 if the directory is changed, and if $PWD is set successfully when
    -P is used; non-zero otherwise.

lvtest@auto-inst:~$ type mkdir
mkdir is /bin/mkdir
lvtest@auto-inst:~$ help mkdir
bash: help: no help topics match `mkdir'.  Try `help help' or `man -k mkdir' or `info mkdir'.
lvtest@auto-inst:~$ mkdir --help
Usage: mkdir [OPTION]... DIRECTORY...
Create the DIRECTORY(ies), if they do not already exist.

Mandatory arguments to long options are mandatory for short options too.
  -m, --mode=MODE   set file mode (as in chmod), not a=rwx - umask
  -p, --parents     no error if existing, make parent directories as needed
  -v, --verbose     print a message for each created directory
  -Z, --context=CTX  set the SELinux security context of each created
                      directory to CTX
      --help     display this help and exit
      --version  output version information and exit

Report mkdir bugs to bug-coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>
Report mkdir translation bugs to <http://translationproject.org/team/>
For complete documentation, run: info coreutils 'mkdir invocation'

lvtest@auto-inst:~$ man 5 passwd
PASSWD(5)                File Formats and Conversions                PASSWD(5)

lvtest@auto-inst:~$ apropos mkdir
mkdir (1)            - make directories
mkdir (2)            - create a directory
mkdirat (2)          - create a directory relative to a directory file descri...

lvtest@auto-inst:~$ whatis ls
ls (1)               - list directory contents

bash-3.2$ ls /usr/bin/ > ls-output.txt
bash-3.2$ ls -l ls-output.txt
-rw-r--r--  1 hfeng  staff  8911 Mar  4 20:43 ls-output.txt
bash-3.2$ ls /usr/bin/ > ls-output.txt
bash-3.2$ ls -l ls-output.txt
-rw-r--r--  1 hfeng  staff  8911 Mar  4 20:43 ls-output.txt

bash-3.2$ ls /usr/bin/ >> ls-output.txt
bash-3.2$ ls /usr/bin/ >> ls-output.txt
bash-3.2$ ls /usr/bin/ >> ls-output.txt
bash-3.2$ ls -l ls-output.txt
-rw-r--r--  1 hfeng  staff  26733 Mar  4 20:44 ls-output.txt

bash-3.2$ ls -l /bin/usr 2> ls-error.txt
bash-3.2$ cat ls-error.txt
ls: /bin/usr: No such file or directory

bash-3.2$ ls -l /bin/usr 2> /dev/null

bash-3.2$ cat > lazy_dog.txt
The quick brown fox jumped over the lazy dog.
bash-3.2$ cat lazy_dog.txt
The quick brown fox jumped over the lazy dog.
bash-3.2$ cat < lazy_dog.txt
The quick brown fox jumped over the lazy dog.

bash-3.2$ ls -l /usr/bin | more | less

bash-3.2$ cat test.txt
a
n
c
n
c
n
1
2
3
4
bash-3.2$ cat test.txt | sort | uniq
1
2
3
4
a
c
n
bash-3.2$ cat test.txt | sort | uniq -d
c
n

bash-3.2$ wc test.txt
      10      10      20 test.txt

bash-3.2$ ls /bin /usr/bin | sort | uniq | wc -l
    1078

bash-3.2$ ls /usr/bin | sort | uniq | grep zip
bunzip2
bzip2
bzip2recover
funzip
gunzip
gzip
unzip
unzipsfx
zip
zipcloak
zipdetails
zipdetails5.16
zipgrep
zipinfo
zipnote
zipsplit

bash-3.2$ head -n 5 ls-output.txt
2to3
2to3-
2to3-2.7
2to32.6
BuildStrings
bash-3.2$ tail -n 5 ls-output.txt
zipsplit
zless
zmore
znew
zprint

bash-3.2$ tail -f /var/log/appstore.log
        "os_updates_to_install_on_restart" = "";
        result = pass;
        "user_initiated" = no;
        "will_restart" = no;
    }
Mar  4 20:29:34 hair.lan storeagent[263]: SoftwareMap: Software map rebuild took 0.0856 seconds for 0 records and produced: {
    }
Mar  4 20:29:34 hair.lan storeagent[263]: AutoUpdateOperation: Released BackgroundTask power assertion (returned 0)
......

bash-3.2$ ls /usr/bin | grep zip | tee out-grep.txt | grep un
bunzip2
funzip
gunzip
unzip
unzipsfx
bash-3.2$ cat out-grep.txt
bunzip2
bzip2
bzip2recover
funzip
gunzip
gzip
unzip
unzipsfx
zip
zipcloak
zipdetails
zipdetails5.16
zipgrep
zipinfo
zipnote
zipsplit

bash-3.2$ ls
Desktop         Downloads       Movies          Pictures        orgblog         tmp
Documents       Library         Music           Public          test            百度云同步盘
bash-3.2$ echo D*
Desktop Documents Downloads
bash-3.2$ echo *s
Documents Downloads Movies Pictures
bash-3.2$ echo [[:upper:]]*
Desktop Documents Downloads Library Movies Music Pictures Public

bash-3.2$ echo ~
/Users/hfeng
bash-3.2$ echo ~root
/var/root

bash-3.2$ echo $((2+2))
4
bash-3.2$ echo $(($((5**2)) * 3))
75

bash-3.2$ echo Front-{A,B,C}-Back
Front-A-Back Front-B-Back Front-C-Back

bash-3.2$ echo Number_{1..5}
Number_1 Number_2 Number_3 Number_4 Number_5
bash-3.2$ echo {Z..A}
Z Y X W V U T S R Q P O N M L K J I H G F E D C B A

bash-3.2$ mkdir {2009..2011}-0{1..9} {2009..2011}-{10..12}
bash-3.2$ ls
2009-01 2009-03 2009-05 2009-07 2009-09 2009-11 2010-01 2010-03 2010-05 2010-07 2010-09 2010-11 2011-01 2011-03 2011-05 2011-07 2011-09 2011-11
2009-02 2009-04 2009-06 2009-08 2009-10 2009-12 2010-02 2010-04 2010-06 2010-08 2010-10 2010-12 2011-02 2011-04 2011-06 2011-08 2011-10 2011-12

bash-3.2$ echo $USER
hfeng
bash-3.2$ printenv
SHELL=/bin/bash
TERM=dumb
TMPDIR=/var/folders/2d/z9f32m_55_71lttsknj0b3980000gn/T/
Apple_PubSub_Socket_Render=/tmp/launch-ymkMDD/Render
LC_ALL=en_US.UTF-8
USER=hfeng
EMACS=t
RBENV_ROOT=/usr/local/var/rbenv
SSH_AUTH_SOCK=/tmp/launch-X7FGUA/Listeners
TERMCAP=
__CF_USER_TEXT_ENCODING=0x1F5:25:52
PAGER=cat
COLUMNS=177
PATH=/usr/local/var/rbenv/shims:/usr/local/bin:/bin:/sbin:/usr:/usr/bin:/usr/sbin:/usr/bin:/bin:/usr/sbin:/sbin
__CHECKFIX1436934=1
PWD=/Users/hfeng/Pics
LANG=en_US.UTF-8
SHLVL=1
HOME=/Users/hfeng
LOGNAME=hfeng
DISPLAY=hair.lan
INSIDE_EMACS=24.3.1,comint
SECURITYSESSIONID=186a5
_=/usr/bin/printenv
OLDPWD=/Users/hfeng

bash-3.2$ ls -l $(which cp)
-rwxr-xr-x  1 root  wheel  24848 Feb  7 21:09 /bin/cp
bash-3.2$ file $(ls /usr/bin/* | grep zip)
/usr/bin/bunzip2:        Mach-O 64-bit executable x86_64
/usr/bin/bzip2:          Mach-O 64-bit executable x86_64
/usr/bin/bzip2recover:   Mach-O 64-bit executable x86_64
/usr/bin/funzip:         Mach-O 64-bit executable x86_64
/usr/bin/gunzip:         Mach-O 64-bit executable x86_64
/usr/bin/gzip:           Mach-O 64-bit executable x86_64
/usr/bin/unzip:          Mach-O 64-bit executable x86_64
/usr/bin/unzipsfx:       Mach-O 64-bit executable x86_64
/usr/bin/zip:            Mach-O 64-bit executable x86_64
/usr/bin/zipcloak:       Mach-O 64-bit executable x86_64
/usr/bin/zipdetails:     a /usr/bin/perl script text executable
/usr/bin/zipdetails5.16: a /usr/bin/perl5.16 script text executable
/usr/bin/zipgrep:        POSIX shell script text executable
/usr/bin/zipinfo:        Mach-O 64-bit executable x86_64
/usr/bin/zipnote:        Mach-O 64-bit executable x86_64
/usr/bin/zipsplit:       Mach-O 64-bit executable x86_64

bash-3.2$ ls -l `which cp`
-rwxr-xr-x  1 root  wheel  24848 Feb  7 21:09 /bin/cp

bash-3.2$ echo 'text ~/*.txt {a, b} $(echo foo) $((2+2)) $USER'
text ~/*.txt {a, b} $(echo foo) $((2+2)) $USER

bash-3.2$ ls -l hello world.txt
ls: hello: No such file or directory
ls: world.txt: No such file or directory
bash-3.2$ ls -l "hello world.txt"
-rw-r--r--  1 hfeng  staff  3 Mar  5 22:07 hello world.txt
bash-3.2$ ls -l 'hello world.txt'
-rw-r--r--  1 hfeng  staff  3 Mar  5 22:07 hello world.txt

bash-3.2$ echo "this is a      test"
this is a      test

bash-3.2$ echo $(cal)
March 2014 Su Mo Tu We Th Fr Sa 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
bash-3.2$ echo "$(cal)"
March 2014
Su Mo Tu We Th Fr Sa
1
2  3  4  5  6  7  8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 29
30 31
bash-3.2$ echo '$(cal)'
$(cal)

bash-3.2$ echo "The balance for user $USER is : \$5.00"
The balance for user hfeng is : $5.00
bash-3.2$ touch good\$work\!
bash-3.2$ ls -l good*
-rw-r--r--  1 hfeng  staff  0 Mar  5 23:16 good$work!

bash-3.2$  history | grep "grep zip"
  448  ls /usr/bin | sort | uniq | grep zip
  451  ls /usr/bin | sort | uniq | grep zip | wc -l
  452  ls /usr/bin | sort | uniq | grep zip
  470  ls /usr/bin | grep zip | tee out-grep.txt | grep un
  504  ls /usr/bin | sort | uniq | grep zip
  505   history | grep grep zip
  506   history | grep "grep zip"
bash-3.2$ !448
ls /usr/bin | sort | uniq | grep zip
bunzip2
bzip2
bzip2recover
funzip
gunzip
gzip
unzip
unzipsfx
zip
zipcloak
zipdetails
zipdetails5.16
zipgrep
zipinfo
zipnote
zipsplit

bash-3.2$ umask 000
bash-3.2$ rm foo.txt
bash-3.2$ > foo.txt
bash-3.2$ ls -l foo.txt
-rw-rw-rw-  1 hfeng  staff  0 Mar  8 12:29 foo.txt
bash-3.2$ rm foo.txt ; umask 0022

bash-3.2$ ps
  PID TTY           TIME CMD
 3970 ttys000    0:00.01 /bin/bash --noediting -i
 3929 ttys006    0:00.01 -bash

bash-3.2$ ps x
  PID   TT  STAT      TIME COMMAND
  145   ??  Ss     0:02.79 /sbin/launchd
  149   ??  S      0:02.93 /usr/libexec/UserEventAgent (Aqua)
  150   ??  S      2:09.42 /usr/sbin/distnoted agent
  152   ??  S      0:02.30 /usr/sbin/cfprefsd agent
  157   ??  S      0:08.60 /System/Library/CoreServices/Dock.app/Contents/MacOS/Dock

bash-3.2$ ps aux
USER              PID  %CPU %MEM      VSZ    RSS   TT  STAT STARTED      TIME COMMAND
hfeng            3848  26.6  3.5  1175648 148560   ??  S    12:57PM   3:05.56 /Applications/Google Chrome.app/Contents/Versions/33.0.1750.117/Google Chrome Helper.app/Contents/M
hfeng             226   9.7  2.2   902680  91836   ??  S     8:11PM  15:07.57 /Applications/Google Chrome.app/Contents/Versions/33.0.1750.117/Google Chrome Helper.app/Contents/M
_windowserver     105   8.2  1.3  3066572  54600   ??  Ss    8:11PM  14:18.16 /System/Library/Frameworks/ApplicationServices.framework/Frameworks/CoreGraphics.framework/Resource
hfeng             205   7.2  3.8  1487564 158904   ??  S     8:11PM  25:21.50 /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

bash-3.2$ ./a.out &
[1] 4130

bash-3.2$ jobs
[1]+  Running                 ./a.out &

bash-3.2$ jobs
[1]   Running                 ./a.out &
[2]   Running                 ./a.out &
[3]-  Running                 ./a.out &
[4]+  Running                 ./a.out &
bash-3.2$ fg %4 # equals==> fg %+ equals==> fg
./a.out

hAir:tmp hfeng$ ./a.out
^Z
[1]+  Stopped                 ./a.out
hAir:tmp hfeng$ jobs
[1]+  Stopped                 ./a.out
hAir:tmp hfeng$ bg %1
[1]+ ./a.out &
hAir:tmp hfeng$ jobs
[1]+  Running                 ./a.out &

Air:tmp hfeng$ ./a.out &
[1] 4214
hAir:tmp hfeng$ kill -1 4214
hAir:tmp hfeng$ jobs
[1]+  Hangup: 1               ./a.out
hAir:tmp hfeng$ ./a.out &
[1] 4215
hAir:tmp hfeng$ jobs
[1]+  Running                 ./a.out &
hAir:tmp hfeng$ kill -INT 4215
hAir:tmp hfeng$ jobs
[1]+  Interrupt: 2            ./a.out
hAir:tmp hfeng$ ./a.out &
[1] 4219
hAir:tmp hfeng$ jobs
[1]+  Running                 ./a.out &
hAir:tmp hfeng$ kill -SIGINT 4219
hAir:tmp hfeng$ jobs
[1]+  Interrupt: 2            ./a.out

bash-3.2$ printenv PATH
/usr/local/var/rbenv/shims:/usr/local/bin:/bin:/sbin:/usr:/usr/bin:/usr/sbin:/usr/bin:/bin:/usr/sbin:/sbin
bash-3.2$ printenv USER
hfeng
bash-3.2$ printenv
SHELL=/bin/bash
TERM=dumb
TMPDIR=/var/folders/2d/z9f32m_55_71lttsknj0b3980000gn/T/
Apple_PubSub_Socket_Render=/tmp/launch-cyv39a/Render
LC_ALL=en_US.UTF-8
USER=hfeng
EMACS=t
RBENV_ROOT=/usr/local/var/rbenv
SSH_AUTH_SOCK=/tmp/launch-6ChvRY/Listeners
TERMCAP=
__CF_USER_TEXT_ENCODING=0x1F5:25:52
PAGER=cat
COLUMNS=167
PATH=/usr/local/var/rbenv/shims:/usr/local/bin:/bin:/sbin:/usr:/usr/bin:/usr/sbin:/usr/bin:/bin:/usr/sbin:/sbin
__CHECKFIX1436934=1
PWD=/Users/hfeng/orgblog/org/notes/bash
LANG=en_US.UTF-8
SHLVL=1
HOME=/Users/hfeng
LOGNAME=hfeng
DISPLAY=hAir.local
INSIDE_EMACS=24.3.1,comint
SECURITYSESSIONID=186a4
_=/usr/bin/printenv

bash-3.2$ set
Apple_PubSub_Socket_Render=/tmp/launch-cyv39a/Render
BASH=/bin/bash
BASH_ARGC=()
BASH_ARGV=()
BASH_LINENO=()
BASH_SOURCE=()
BASH_VERSINFO=([0]="3" [1]="2" [2]="51" [3]="1" [4]="release" [5]="x86_64-apple-darwin13")
BASH_VERSION='3.2.51(1)-release'
COLUMNS=167
DIRSTACK=()
DISPLAY=hAir.local
EMACS=t
EUID=501
GROUPS=()
HISTFILE=/Users/hfeng/.bash_history
HISTFILESIZE=500
HISTSIZE=500
HOME=/Users/hfeng
HOSTNAME=hAir.local
HOSTTYPE=x86_64
IFS=$' \t\n'
INSIDE_EMACS=24.3.1,comint
LANG=en_US.UTF-8
LC_ALL=en_US.UTF-8
LOGNAME=hfeng
MACHTYPE=x86_64-apple-darwin13
MAILCHECK=60
OPTERR=1
OPTIND=1
OSTYPE=darwin13
PAGER=cat
PATH=/usr/local/var/rbenv/shims:/usr/local/bin:/bin:/sbin:/usr:/usr/bin:/usr/sbin:/usr/bin:/bin:/usr/sbin:/sbin
PIPESTATUS=([0]="0")
PPID=12271
PS1='\s-\v\$ '
PS2='> '
PS4='+ '
PWD=/Users/hfeng/orgblog/org/notes/bash
RBENV_ROOT=/usr/local/var/rbenv
SECURITYSESSIONID=186a4
SHELL=/bin/bash
SHELLOPTS=braceexpand:hashall:histexpand:history:interactive-comments:monitor
SHLVL=1
SSH_AUTH_SOCK=/tmp/launch-6ChvRY/Listeners
TERM=dumb
TERMCAP=
TMPDIR=/var/folders/2d/z9f32m_55_71lttsknj0b3980000gn/T/
UID=501
USER=hfeng
_=set
__CF_USER_TEXT_ENCODING=0x1F5:25:52
__CHECKFIX1436934=1
_rbenv ()
{
    COMPREPLY=();
    local word="${COMP_WORDS[COMP_CWORD]}";
    if [ "$COMP_CWORD" -eq 1 ]; then
        COMPREPLY=($(compgen -W "$(rbenv commands)" -- "$word"));
    else
        local words=("${COMP_WORDS[@]}");
        unset words[0];
        unset words[$COMP_CWORD];
        local completions=$(rbenv completions "${words[@]}");
        COMPREPLY=($(compgen -W "$completions" -- "$word"));
    fi
}
rbenv ()
{
    typeset command;
    command="$1";
    if [ "$#" -gt 0 ]; then
        shift;
    fi;
    case "$command" in
        rehash | shell)
            eval `rbenv "sh-$command" "$@"`
        ;;
        *)
            command rbenv "$command" "$@"
        ;;
    esac
}

bash-3.2$ echo $HOME
/Users/hfeng

hfeng@harrifeng ~]$ alias
alias ls='ls --color=auto'

 1: # .bash_profile
 2: 
 3: # Get the aliases and functions
 4: if [ -f ~/.bashrc]; then
 5:     . ~/.bashrc
 6: if
 7: 
 8: # User specific environment and startup programs
 9: PATH=$PATH:$HOME/bin
10: export PATH

bash-3.2$ source .bashrc

lvtet@auto-inst: rpm -qf /usr/bin/vim