Delete whitespace in each begin of line of file, using bash

Question

How i can delete whitespace in each line of file, using bash For instance, file1.txt. Before:

  gg g
 gg g
t  ttt

after:

gg         


        

Answer 1

"Whitespace" can include both spaces AND tabs. The solutions presented to date will only match and operate successfully on spaces; they will fail if the whitespace takes the form of a tab.

The below has been tested on the OP's specimen data set with both spaces AND tabs, matching successfully & operating on both:

sed 's/^[[:blank:]]*//g' yourFile

After testing, supply the -i switch to sed to make the changes persistent-