000211-3

The RFC822 date format will in the future be changed in the following ways:

  1. Specify more clearly that one or more LWSP characters are allowed between "Date:" and the value.
  2. Exactly one space between the elements in the date-time specification.
  3. Only numerical time-zones allowed.
  4. A comment inside parenthesis is allowed, but only after the end of the date-time.
  5. Four-digit years.

Specify in ABNF format the new format for the "Date:" header.

Answer

 
date        =  "Date:" CWSP date-time

date-time   =  [ day ", " ] date " " time     ; dd mm yy
                                              ;  hh:mm:ss zzz

 day         =  "Mon"  / "Tue" /  "Wed"  / "Thu"
             /  "Fri"  / "Sat" /  "Sun"

 date        =  1*2DIGIT " " month " " 4DIGIT ; day month year
                                              ; e.g. 20 Jun 1982

 month       =  "Jan"  /  "Feb" /  "Mar"  /  "Apr"
             /  "May"  /  "Jun" /  "Jul"  /  "Aug"
             /  "Sep"  /  "Oct" /  "Nov"  /  "Dec"

 time        =  hour zone

 hour        =  2DIGIT ":" 2DIGIT [":" 2DIGIT]
                                       ; 00:00:00 - 23:59:59

 zone        =  ("+" / "-") 4DIGIT        ; Local differential
                                          ;  hours+min. (HHMM)

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