zelonWiki: Linux Shell Programming

if (조건)
''commands''
then
''commands''
fi

case (값) in
(조건)) commands;;
(조건)) commands;;
esac

while
''command''
do
''commands'';;
done

-d file	The specified file exists and is a directory.
-e file	The specified file exists.
-r file	The specified file exists and is readable.
-s file	The specified file exists and has non-zero size.
-w file	The specified file exists and is writable.
-x file	The specified file exists and is executable.
-L file	The specified file exists and is a symbolic link.
f1 -nt f2	File f1 is newer than file f2.
f1 -ot f2	File f1 is older than file f2.
-n s1	String s1 has nonzero length.
-z s1	String s1 has zero length.
s1 = s2	String s1 is the same as string s2.
s1 != s2	String s1 is not the same as string s2.
n1 -eq n2	Integer n1 is equal to integer n2.
n1 -ge n2	Integer n1 is greater than or equal to integer n2.
n1 -gt n2	Integer n1 is greater than integer n2.
n1 -le n2	Integer n1 is less than integer n2.
n1 -lt n2	Integer n1 is less than or equal to integer n2.
n1 -ne n2	Integer n1 is not equal to integer n2.
!	The not operator, which reverses the value of the following condition.
-a	The and operator, which joins two conditions. Both conditions must be true for the overall result to be true.
-o	The or operator, which joins two conditions. If either condition is true, the overall result is true.
\( ... \)	You can group expressions within the test command by enclosing them within \( and \).