i want to extract lines 5 and 7 from a txt file which contains nearly 20 entries how to do it
also i want to check whether the 42nd character is 'S' in that line

suggestions welcome

Do you want to extract both lines in same command?

no not needed
in different commands

take some inspiration from here

see here if you are using bash.
under "substring extraction". then check with if/else statement

Hi TrichySelva,
Sorry for Late response(Actually I joined this forum today itself!!)
To extract line number 5 and 7,use:
bash-2.03# sed -n '5p;7p' cricketnews
5 and if Pakistan, as expected, beat Bangladesh the day after,
7 the virtue of having won more matches in the Super Four stage, Pakistan will go through.

To Extract Say Line 4-6,12-15 and 32 to last,do this:
bash-2.03# sed -n '4,6p;12,15p;32,$p' cricketnews
4 ousted from the event. If India lose to Sri Lanka on Thursday,
5 and if Pakistan, as expected, beat Bangladesh the day after,
6 both teams will be tied on four points. In that scenario, by
12 the CB Series in Australia. Therein lies the story: the CB
13 Series was played in Australia, the Asia Cup is being
14 played in Pakistan. And the Indian bowlers react differently
15 to the two types of conditions.
32 to struggle on pitches that give him zero assistance.
33 Dhoni thought the bowlers gave it their all, but
34 the pitch was just too unresponsive.

To Extract say 25th to 30th(To extract 42nd char-just write 42) char and 34-38char of each of these lines,
bash-2.03# sed -n '4,6p;12,15p;32,$p' cricketnews|cut -c25-30,34-38
eventf Ind
, as ected,
be tion fo
in Auslia.
yed instral
stan. the
es of ditio
pitchthat
the bors ga
just tunres

bash-2.03# sed -n '4,6p;12,15p;32,$p' cricketnews|cut -c42
l
a
p
r

i

e
i
s

Hope it solves ur purpose,though sadly bit too late I believe

Sujan Banerjee