Bash notes_1

String operations
Goal: isolate something useful from a string, short or long, also multi-line.
Operators:

• # delete from left to the first case of what follow
• ## delete from left to the last case of what follow
• % delete from right to the first case of what follow
• %% delete from right to the last case of what follow

Example

x="this is a test string"

echo ${x#*is}

echo ${x##* }

echo ${x%test*}

echo ${x%% *}

prints

is a test string

string

this is a 

this

All clear?!?

Goal: Select substring from a string
How: ${string:starting_point:offset}
Estract the substring from starting_point position of string for a number of offset char.
Example
x="example string"
echo ${x:2:4}
echo ${x:8:1}
prints
ampl
s