simple sed -n problem

[Guest_imported]

Friends , a stupid question.
Following is the file of 9 lines (sample.txt) :
900
12356
2.1
3.14159265
87878787
0.25


a

if i give command ,
sed -n -e '/900*/p' sample.txt
I get output of just one line ,
900

Now if I give command ,
sed -n -e '/[09]*/p' sample.txt
I get all the lines in output ,
900
12356
2.1
3.14159265
87878787
0.25


a

Why is that ?? I am expecting combination of only 0 & 9 in output .
Please advice.

 

[vgersh99]

sed -n -e '/[09]/p'

By specifying '*' you're saying 'ZERO or more occurences of the preceeding character' [0 or 9 in your case]. It outputs everything because of the 'ZERO' case. vlad
+---------------------------+
|#include<disclaimer.h> |
+---------------------------+

 

[bigscouse]

try: - sed -n -e '/[0-9].*/'
Ged Jones

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