UNIX for Beginners Questions & Answers

Anything that will always sort higher than any value that can appear in the time field you're processing. If you were processing dates of the form YYYY/MM/DD HH:MM:SS you might choose something like 9999/99/99 99:99:99 and for a date of the form mmmmmmmm you might choose something like 99999999, but since digits sort before any uppercase alphabetic value in the POSIX Locale (and in most other locales), you could just as easily choose T[date_field_num]="A" (where date_field_num is the field number for the field you are comparing).

It denotes a date value to be used for comparisons to date fields in file2 once end-of-file has been encountered on file1.

Thanks you Don!