My input has a mix of tabs and spaces for readability. I want to modify a field using perl -a, then print out the line in its original form. (The data is from findup, showing me a count of duplicate files and the space they waste.) Input is:
2 * 4096 backup/photos/photo.jpg photos/photo.jpg
2 * 111276032 backup/books/book.pdf book.pdf
The output would convert field 3 to kilobytes, like this:
2 * 4 KB backup/photos/photo.jpg photos/photo.jpg
2 * 108668 KB backup/books/book.pdf book.pdf
In my dream world, this would be my code, since I could just will perl to automatically recombine @F and preserve the original whitespace:
perl -lanE '$F[2]=int($F[2]/1024)." KB"; print;'
In real life, joining with a single space seems like my only option:
perl -lanE '$F[2]=int($F[2]/1024)." KB"; print join(" ", @F);'
Is there any automatic variable which remembers the delimiters? If I had a magic array like that, the code would be:
perl -lanE 'BEGIN{use List::Util "reduce";} $F[2]=int($F[2]/1024)." KB"; print reduce { $a . shift(@magic) . $b } @F;'