UNIX Commands

Sort

The command sort is used to sort files line by line.  Lines starting with a number go first. Lines that come next in order go alphabetical with uppercase letters appearing before lowercase ones.

Use cat to create “testsort” for the example.

~/Test>cat testsort
A line 1
a line 2
8 line 3
line 4
5 line 5
~/Test>sort testsort
5 line 5
8 line 3
A line 1
a line 2
line 4

R sorts by using a random hash of keys

~/Test>sort -R testsort
a line 2
5 line 5
A line 1
8 line 3
line 4
~/Test>sort -R testsort
5 line 5
A line 1
a line 2
line 4
8 line 3

Egrep & Fgrep

EGREP:

            The Command egrep is the same as running grep –E. egrep is used to search for a pattern using extended regular expressions.

Terry@f:~/FinderDing>cat testsort
A line 1	
a line 2	
8 line 3	
line 4
5 line 5	
Terry@f:~/FinderDing>egrep '^[a-zA-Z]' testsort	
A line 1
a line 2
line 4

*Show lines that start with a letter from alphabet

Terry@f:~/FinderDing>cat html
<!DOCTYPE html>
<html>	
<body>
<h1>My First Heading</h1>
<p>My first paragraph.</p>
</body>
</html>
Terry@f:~/FinderDing>egrep "My|first" html
<h1>My First Heading</h1>
<p>My first paragraph.</p>

`*Find lines with pattern My first from html file

FGREP:

The command fgrep is the same as running grep –F. The Command searches for fixed character strings in a file, which means regular expressions can’t be used.

Terry@f:~/FinderDing>fgrep "My" html
<h1>My First Heading</h1>
<p>My first paragraph.</p>l
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