5일째 정리 - 쉘, 입력, 출력

bash-3.2$ ls
AAA

bash-3.2$ cat AAA BBB
hoge
cat: BBB: No such file or directory

bash-3.2$ cat AAA BBB > out.txt
cat: BBB: No such file or directory
bash-3.2$ cat out.txt 
hoge

bash-3.2$ cat AAA BBB 2> error.txt
hoge
bash-3.2$ cat error.txt 
cat: BBB: No such file or directory

bash-3.2$ cat AAA BBB|cat
cat: BBB: No such file or directory
hoge

쉘 스크립트 및 환경 변수, 쉘 변수

bash-3.2$ printenv|nl
     1  TERM_PROGRAM=Apple_Terminal
（省略）
    18  OLDPWD=/Users/nekonisi

bash-3.2$ env|nl
     1  TERM_PROGRAM=Apple_Terminal
（省略）
    18  OLDPWD=/Users/nekonisi

bash-3.2$ set|nl
     1  BASH=/bin/bash
（省略）
    48  _=

bash-3.2$ hoge="test"
bash-3.2$ export fuga="test2"
bash-3.2$ echo $hoge
test
bash-3.2$ echo $fuga
test2
bash-3.2$ bash

The default interactive shell is now zsh.
To update your account to use zsh, please run `chsh -s /bin/zsh`.
For more details, please visit https://support.apple.com/kb/HT208050.
bash-3.2$ echo $hoge

bash-3.2$ echo $fuga
test2

bash-3.2$ cat test.sh 
#!/bin/bash
echo $hoge
bash-3.2$ hoge='hogeeee'
bash-3.2$ bash test.sh 

bash-3.2$ source test.sh 
hogeeee
bash-3.2$ ./test.sh
bash: ./test.sh: Permission denied
bash-3.2$ chmod +x test.sh 
bash-3.2$ ./test.sh
bash-3.2$ echo $?
0