(1) s1 = s2
(2) s1 != s2
(3) s1 < s2
(4) s1 > s2
(5) -n s1
(6) -z s1
(1) s1 matches s2
(2) s1 does not match s2
(3) __TO-DO__
(4) __TO-DO__
(5) s1 is not null (contains one or more characters)
(6) s1 is null
Comparing two strings.
#!/bin/bash
S1='string'
S2='String'
if [ $S1=$S2 ];
then
echo "S1('$S1') is not equal to S2('$S2')"
fi
if [ $S1=$S1 ];
then
echo "S1('$S1') is equal to S1('$S1')"
fi
+
-
*
/
% (reminder)
-lt (<)
-gt (>)
-le (<=)
-ge (>=)
-eq (==)
-ne (!=)
C programmer's should simple map the operator to its corresponding parenthesis.
sed (stream editor - very useful)
gawk
grep (show line matching this or not matching that)
wc (count words, lines)
sort
bc (more than a calculator)
cut (edit columns)
tput (get information from the current terminal)
It it higly recommended to be familiarized with this programs (at least). There are tons of little programs that will let you do real magic in a command line.