Why would anyone ever write an awk script? This one converts some parts of an ics calender file to the remind format.

ics2rem.awk

#!/usr/bin/awk -f
# ics2rem by Hinnerk Haardt <hinnerk@randnotizen.de>
#
# Converts output of iCalendar to remind
# usage: cat FILENAME.ics | rem2ics > reminders.rem
#
# THE FOLLOWING CODE IS RELEASED INTO THE PUBLIC DOMAIN
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE

BEGIN { 
  RS = "\n"
  FS = ":"
  ORS = " "
  # names of months
  month["01"] = "Jan"
  month["02"] = "Feb"
  month["03"] = "Mar"
  month["04"] = "Apr"
  month["05"] = "May"
  month["06"] = "Jun"
  month["07"] = "Jul"
  month["08"] = "Aug"
  month["09"] = "Sep"
  month["10"] = "Okt"
  month["11"] = "Nov"
  month["12"] = "Dec"
  # timezones (not used, for further reference)
  timezone["Europe/Berlin"] = "-2"
  }

{
  if ($1 == "END" && $2 == "VEVENT") {
      
    # DESCRIPTION
    if (event["vevent","DESCRIPTION"]!="")
      event["vevent","DESCRIPTION"] = (" (" event["vevent","DESCRIPTION"] ")")
      
    # STARTDATE
    for (option in event) {
      if (option ~ /^vevent.*DTSTART.*/)
        startdate["full"] = event[option]
      # DTSTART sometimes contains additional information...
      if (option ~ /^vevent.*DTSTART;.*/) {
        split(option, dtstarttrasharray, ";" )
        # ... that sometimes is the timezone
        if (dtstarttrasharray["2"] ~ /^TZID.*/) {
          split(dtstarttrasharray["2"], localtimezonearray, "=")
          startdate["timezone"] = localtimezonearray["2"]
        }
        # clean up
        split("", localtimezonearray)
        split("", dtstarttrasharray)
      }
      startdate["year"]   = substr(startdate["full"],0,4)
      startdate["month"]  = substr(startdate["full"],5,2)
      startdate["day"]    = substr(startdate["full"],7,2)
      if (startdate["full"] ~ /.*T.*/) {
        startdate["hour"]   = substr(startdate["full"],10,2)
        startdate["minute"] = substr(startdate["full"],12,2)
        startdate["second"] = substr(startdate["full"],14,2)
        if (startdate["hour"] != "00")
          # no seconds exported... (startdate["second"])
          startdate["time"] = ("AT " startdate["hour"]":" startdate["minute"])
          
      }
      startdate["remind"] = (month[startdate["month"]] " " startdate["day"] " " startdate["year"] " " startdate["time"])
    }
      
    # DURATION
      if (option == "DURATION") {
        duration = event[option]
        # ... and adjusted.
        # !FIXME: Format: "P[numD]T[numH][numM]", "num" is a integer 
        #sub([0-9*d], womit, duration)
        duration = (" " duration)
        }


        # !TODO: ATTENDEE, X-WR-ALARMID:SOUNDALARM, ACTION,
        #        ATTACH, X-WR-ALARMID:DISPLAYALARM, TRIGGER
        #        STATUS, SEQUENCE(?, Timezone Array calc(?),
        #        

    
    # !FIXME calculate: startdate + DURATION => enddate

  # print the remind line
    print "REM " startdate["remind"] " MSG " event["vevent","SUMMARY"] event["vevent","DESCRIPTION"] "\n"

  # clean up vars and arrays:
    split("", event)
    split("", startdate)
    
  }
  
  else
    # !FIXME: Ungetestet, soll EVENT und ALARM voneinander unterscheidbar machen:
    # !FIXME: Muß noch oben geändert werden, wenn es funktioniert.
    if ($1 == "BEGIN" && $2 == "VALARM")
      arrayname = "valarm"
    if ($1 == "BEGIN" && $2 == "VEVENT")
      arrayname = "vevent"
    event[arrayname,$1] = $2
}

# END {}