Question

Why is it so hard to do sed like operation in Python?

cat temp$$ | sed '/ENTRY/d' | sed '/VERSION/d' > temp$$1

The following attempt simply doesn’t work (instead of writing to file I’m printing to screen):

 70 for line in open("temp5027", 'r'):
 71     
 72     if re.search("ENTRY|VERSION", line) != None:
 73         pass
 74     else:
 75         print line

A frustrated first time python user.

Note: I’m using python 2.4 so no “with” support yet.

Answer 1

Write to file with Python 2.4

import re

i = open("in.txt")
o = open("out.txt", "w")

for line in i:
    if re.search("ENTRY|VERSION", line):
       o.write(line)

o.close()
i.close()

Write to file with modern Python

import re

with open("in.txt") as i, open("out.txt", "w") as o:
    for line in i:
        if re.search("ENTRY|VERSION", line):
           o.write(line)

Bonus

Improve your sed usage.

$ sed -e '/ENTRY/d' -e '/VERSION/d' < in.txt > out.txt