shell question: pad end of each line with spaces to = 80 chars ??

konsolebox · 04-17-2011, 04:17 AM

also, if the OP wants a wrapping version:

Code:

#!/bin/bash

SPACES='                                                                                '

while read LINE; do
    while I=${#LINE}; [[ I -gt 80 ]]; do
        echo "${LINE:0:80}"
        LINE=${LINE:80}
    done

    if [[ I -eq 80 ]]; then
        echo "$LINE"
    else
        echo "$LINE${SPACES:0:80 - I}"
    fi
done

or less logic consistent but simpler form

Code:

#!/bin/bash

SPACES='                                                                                '

while read LINE; do
    while I=${#LINE}; [[ I -gt 80 ]]; do
        echo "${LINE:0:80}"
        LINE=${LINE:80}
    done

    echo "$LINE${SPACES:0:80 - I}"
done

di11rod · 04-21-2011, 05:59 PM

Wow. I am really impressed at the response I've received to this request for help. This is amazing. I wish to extend a BIG thanks to everyone who chimed in here with advice.

I've applied the AWK suggestion provided by Telengard, but there seem to be a bit of unexpected output in the resulting file. From what I can tell, there are now 80 characters on each line, but embedded at the end of the real text on each line is a ^M, which looks like a linefeed. I didn't get that on my other set of files that I applied the AWK command against. Just this one batch.

Code:

awk '{printf "%-80s\n", $0}' onefile > twofile

The recipient of this file is trying to import it into some kind of system that expects a very strict format of data being at exact character locations. The import failed and I'm wondering if it's due to these embedded ^M characters. Does anyone know how I can scrub these from the output?

Screen capture attached.

Thanks again for the help provided thus far and for any additional help you may send my way.

Appreciatively,

di11rod

MTK358 · 04-21-2011, 06:12 PM

Quote:

Originally Posted by di11rod

've applied the AWK suggestion provided by Telengard, but there seem to be a bit of unexpected output in the resulting file. From what I can tell, there are now 80 characters on each line, but embedded at the end of the real text on each line is a ^M, which looks like a linefeed. I didn't get that on my other set of files that I applied the AWK command against. Just this one batch.

That's becasue you're using Windows.

Linux uses linefeeds to separate lines, Windows does it differently (carriage return followed by linefeed).

theNbomr · 04-21-2011, 06:38 PM

Usually, ^M's (carriage returns) are a result of editing the file with a DOS-oriented tool. Sometimes Linux editors (nedit, for example) can read and/or write in DOS end-of-line format, so you might try an editor in your collection. There are also various small tools around that convert between DOS and Unix. This should also work:

Code:

tr -d '\r' < dosfile > unixfile

--- rod.

Telengard · 04-21-2011, 07:03 PM

I'm not exactly certain why this is happening, but Windows' 0x0d 0x0a line endings are most likely complicating things. I wonder what will happen if you try this.

Code:

awk 'BEGIN {RS = "\r\n"} {printf "%-80s\n", $0}' onefile > twofile