UNIX for Beginners Questions & Answers

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K 0998703000000000000190510095351019500020005101480         
CC0338703368396368396190510114449019600010005101980301      
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I O553203000000000000190510120433019700010005101980301

9987_190510.txt
3387_190510.txt
5532_190510.txt

awk '{ F=substr($0,4,4)".txt"; print $0 >> F; close(F) }' filename

awk '
/^.{3}9987.{14}190510/  {print >"file1"}
/^.{3}3387.{14}190510/  {print >"file2"}
/^.{3}5532.{14}190510/  {print >"file3"}
' file

awk '{ F=substr($0,4,4) "_" substr($0,21,6) ".txt"; print $0 >> F; close(F) }' filename

awk '{print > gensub(/^.{3}(.{4}).{14}(.{6}).*/, "\\1_\\2", 1)".txt"}'

#!/bin/bash
outfile="" prefile=""
while IFS= read line
do
  outfile="${line:3:4}_${line:21:6}.txt"
  if [ "$outfile" != "$prefile" ]
  then
    exec >>"$outfile"
    prefile=$outfile
  fi
  echo "$line"
done < filename

awk '{ F=substr($0,4,4) "_" substr($0,22,6) ".txt"; print $0 >> F } F!=PF { close(PF); PF=F }' filename

awk '{ F=substr($0,4,4) "_" substr($0,22,6) ".txt"; print $0 > F }' filename