question on replacing blanks with other values

[Narasimham]

How is it possible(in awk or shell programming) to replace blank lines in a file with some other charecter like "0".


Thanks
Narasimham

[Pete Randall]

sed 's/" "/"0"/'

Pete

[Paula J Frazer-Campbell]

Hi

This Word doc should help:-

Paula

[Pete Randall]

Oops, sorry, don't need quotes: sed 's/ /0/'

Pete

[Paula J Frazer-Campbell]

Hi Pete

Sorry that will replace blank spaces - question is blank LINES ?

A blank line could contain many spaces or unprintable chars.


Perhaps an example of the file will help more - can you attach one?

Paula

[Pete Randall]

Geez, I'm sorry. I wish I could blame it on Monday but that's not even close. But thanks for pointing it out, Paula.

Pete

[Shahul · Accepted solution]

Hi

This command will replace all blank lines in a file to "y".

#sed s/^$/y/g file

Here "s" is for replacing
"^$" represents blank line
"g" is for global replacement. If g is not there, it will replace only the first occurence of blank line.

I hope now U are clear.

Best of luck
Shahul

[James R. Ferguson]

Hi:

Treating blanks, tabs and newline characters and their combinations as "blank" lines, you can do:

# sed -e 's/^[ ]*/0/'

Note that this is typed as "[", a blank (space) character, a tab character and a "]".

Regards!

...JRF...
#

[MANOJ SRIVASTAVA]

Hi Narsimhan

cat filenaem | sed -e "1,$ s / /0/g "

the tip is that try it in vi mode and then use the same string in quotes with sed -e , most of the time it works cool.


Manoj Srivastava

[A. Clay Stephenson]

Plan B.

tr ' ' '0' < oldfile > newfile

[A. Clay Stephenson]

Sorry, forget my Plan B. I read your title rather than reading the question.

[Pete Randall]

Try blaming it on Monday, Clay.

;^)

Pete

[Paula J Frazer-Campbell]

Hi Pete

Isn't it Monday then ----

It certainly feels like it.


Paula

[Pete Randall]

Hi Paula,

I was off yesterday. Maybe that's why it seems like Monday but then, don't they all? I didn't think that would disable my ablity to read my native language but you never know, I guess.

Pete

[James R. Ferguson]

Hi (again):

Oops, Monday is must be for me too! I dropped the "$" anchor:

# sed -e 's/^[ ]*$/0/'

Again, note that this is typed as "[", a blank (space) character, a tab character and a "]".

By the same token:

# sed 's/^$/0/g'

...should also be:

# sed 's/^$*/0/g'

Regards!

...JRF...