deleting white spaces


 
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# 1  
deleting white spaces

How would I delete white spaces in a specified file?

Also, I'd like to know what command I would use to take something off a regular expression, and put it onto another.
ie.
.
.
.
expression1 <take_off>
.
.
.
expression2 (put here)
.
.
.
Any help would be great, thanks!
# 2  
For the first part, please search the forums for removing or deleting whitespace (blank lines, etc)... many people have asked this, such as here:

https://www.unix.com/shell-programming-and-scripting/11400-remove-whitespace-test.html?s=
https://www.unix.com/shell-programming-and-scripting/10336-removing-whitespace-files.html?s=
https://www.unix.com/shell-programming-and-scripting/11770-leading-trailing-spaces.html?s=

And many, many others! Smilie

As for the second, I kinda have an idea of what you're talking about, but I'm not entirely sure. Post a concrete example of what you're trying to do... just remove a few words off the end of one sentence and paste them on the end of another?
# 3  
Ok, this is what I'm trying to do
--------------------------------------------------------------------
before:
...
...
<unique expression1 here> XXX
...
...
...
<another unique expression2 here>
...
...
---------------------------------------------------------------------
after:
...
...
< unique expression1 here>
...
...
...
<another unique expression2 here> XXX
...
...
# 4  
you can define the befor or after text. you have to know what your looking for befor you can look for it.

IE: /text_befor_uniq_regx[REGEX](textafter REGEX)rest_of_line/
$save=$1;
/(text_befor_uniq_regx[REGEX])/$1 $save/

something like that.
# 5  
Like Optimus_P said ... how do you know where in the file you want to delete text and where you want to insert it?

Because we need to identify where <unique expression1 here> is and then grab the text after that; then identify where <another unique expression2 here> is and insert the text we grabbed.

But will expression2 always come after expression1?
# 6  
Oh, i'm sorry, you know what the unique expressions are.
# 7  
Try this code. It's inefficient and makes four passes on the file (one for grep and three for sed), but:
  • 1) Pulls the text you're moving from the first expression to the second.
  • 2) Actually removes the text you're moving from the first expression
  • 3) Moves the text to the end of the second expression.
Code:
express1="first expression you search for"
express2="second expression you search for"

tomove=`grep "^$express1" myfile | sed 's/^'$express1'//'`

sed 's/^'$express1$tomove'/'$express1'/' myfile > tmpfile

sed 's/^'$express2'/'$express2$tomove'/' tmpfile > myfile

 

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