Hello, been a while since my last visit.

Looking for a simple (hopefully) way of subtracting one hour from date - time in a file.

The file is a text file of the following format:

2016-05-16 10:51:07 random text1

2016-05-16 11:58:37 random text2

2016-05-16 12:01:49 random text3

All the times are during the daytime so I do not have to worry about "role-over" at midnight.

I simply want to change the above to

2016-05-16 09:51:07 random text1

2016-05-16 10:58:37 random text2

2016-05-16 11:01:49 random text3

I have BBEdit which will run Perl and on a Mac with the latest Perl modules that come with the OS.

In reply to Date/Time Manipulation by RobertJ

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