mjhjmtu

I was wondering if there's any command to look for blank field values of a text file and remove the entire line.

Example

 Hello:Its Me
 Hello:How are you
 Hello:
 Hello:Bye

And expected output

 Hello:Its Me
 Hello:How are you
 Hello:Bye

Very standard case, the simplest solution with awk would be

awk -F: '$2 != ""' file

and with grep:

grep :. file 

If you mean to skip Hello: lines you can use something like:

awk -F: 'if($2 != "") print ' input_file 

At least with GNU awk, and I think with any version of awk, the default action when something evaluates to true is to print. So, if you set the field delimiter to :, to print lines that have a second field, all you need is:

$ awk -F: '$2' file
Hello:Its Me
Hello:How are you
Hello:Bye

However, this will also print cases where the second field is whitespace (a space, or a tab etc), but will not print the line if second field is one or multiple 0s, because awk evaluates this as false.

Sometimes it is easier to define the remove conditions (grep -v). Example remove when last field is empty:

grep -v ':$' file