Issue
A series of file names should be in format:
ABCDEF - XY1234 - FileName.ext
(The middle section is fixed length (2 alpha + 4 numeric), the first and last sections can be longer or shorter than the example. The extension will always be three alphanumeric characters.)
However, some files do not have the hyphens surrounded by spaces:
EFGHI- WX2345 -FileName.ext
JKLMN-VW3456 - FileName.ext
OPQRS - UV4567- FileName.ext
Is there a way to replace all these combinations "X -X", "X-X", and "X- X" with "X - X" using sed?
(I have tried the pattern of a non-whitespace character followed by a hyphen - '\S\-' as my pattern, but replacing this with a space followed by the hyphen '\ \-' then means I lose the character represented by the '\S'. Had this worked my intention would have been to pass each filename through the three variations to ensure compliance.)
Solution
Is there a way to replace all these combinations "X -X", "X-X", and "X- X" with "X - X" using sed?
You may use this sed:
sed -E 's/[[:blank:]]*-[[:blank:]]*/ - /g' file
EFGHI - WX2345 - FileName.ext
JKLMN - VW3456 - FileName.ext
OPQRS - UV4567 - FileName.ext
Breakdown:
[[:blank:]]*-[[:blank:]]*: matches-surrounded by 0 or whitespaces on both sides-: replaced that with-surrounded by a single space on both sides
An awk solution would be:
awk -F '[[:blank:]]*-[[:blank:]]*' -v OFS=' - ' '{$1=$1} 1' file
EFGHI - WX2345 - FileName.ext
JKLMN - VW3456 - FileName.ext
OPQRS - UV4567 - FileName.ext
or even this:
awk '{gsub(/[[:blank:]]*-[[:blank:]]*/, " - ")} 1' file
Answered By - anubhava Answer Checked By - Mildred Charles (WPSolving Admin)