Shell Programming and Scripting

Hi All,
Can Anyone please tell me,how can I delete a line from a file.
I am reading the file line by line using whil loop and validating each line..Suppose in the middle i found a particular line is invalid,i need to delete that particular line.
Can anyone please help.
Thanks in advance,
Dinesh

you may redirect the output to a new file, while writing all the lines in the loop except for the ones you dont want...else
try sed, grep, awk anything.

Thanks for ur reply..
Can you please help me in writing the command using sed/awk. I am a beginner in UNIX.

search for the awk or sed manual...
atleast give some try...

I have tried with sed -i and sed -d ..but it is not working

show your code.
sample input,
validation pattern, and
expected output

input file
First Name - position from 1-5
Last Name- position 6-10
Age-Position 11-12
Say above is the format of input file.
Example:
DINESKUMAR21
SACHISHAH 23
23
GURUNTARIM22

In the above example,in the 3 rd record Name is missing. Now while reading the file line by line,I want to delete the 3 rd line during validation.

---------- Post updated at 08:47 AM ---------- Previous update was at 08:46 AM ----------

for the third line blankspaces will be present before 23