I am trying to find datatime stamps that have an incorrect timezone due to Daylight Savings Time (starting or ending). If the timezone is incorrect, I want to replace it with the correct timezone for those matches.
e.g. 2024-03-10T00:15:00-07:00 = 2024-03-10T00:15:00-08:00
I came up with the following regex and am able to find the culprits in the file using grep:
grep -E '~2024-03-10T[01]{2}:[0-9]{2}:[0-9]{2}-07:00' <filename>
I am trying to do the substitution using sed and the regex I came up with, but I can't seem to get it to work correctly.
Here's what I currently have:
sed 's/\(~2024-03-10T[01]{2}:[0-9]{2}:[0-9]{2}\)-07:00~/\1-08:00~/g' filename
What am I missing? This command does not seem to make any substitutions. Any help would be appreciated! Thanks in advance!
Setup:
$ cat filename
~2024-03-09T00:15:00-07:00~ some text
~2024-03-10T00:15:00-07:00~ some text
~2024-03-11T00:15:00-07:00~ some text
I tend to use -E to enable support for extended regexes and to simplify the capture group syntax.
This requires just a couple small changes to your current code:
sed -E 's/(~2024-03-10T[01]{2}:[0-9]{2}:[0-9]{2})-07:00/\1-08:00/g' filename
^^ ^ ^
Where:
-E - enable support for extended regexes( | ) - no need to escape the parens (capture group delimiters)This generates:
~2024-03-09T00:15:00-07:00~ some text
~2024-03-10T00:15:00-08:00~ some text
~2024-03-11T00:15:00-07:00~ some text