There are a lot of ways to change the amount of white space (space and tab characters) in a line:
Berkeley systems have cat -s ( 25.10 ) to replace sets of two or more blank lines with single blank lines. If you don't have cat -s or need something different, look at article 34.18 .
The crush ( 25.11 ) script removes all blank lines.
Use doublespace and triplespace ( 25.12 ) to double- and triple-space text.
The pushin ( 25.13 ) script replaces multiple white space characters with a single space. This can shorten long lines.
You can use sed to indent lines of text before printing ( 43.9 ) . The offset ( 35.7 ) shell script does that more easily.
For other jobs, utilities like awk ( 33.11 ) and sed ( 34.24 ) will probably do what you want. You have to understand how to program them before you use them.
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