Shell Programming and Scripting

DEV> vi dateformat.sh
#!/bin/ksh
cur_date="${1:-2013/03/13 13:24:50}"
printf "Processing date: %s\n" "$cur_date"
amn="JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC"
y=${cur_date%%/*}
m=${cur_date:5:2}
dm=${m#0}
d=${cur_date:8:2}
t=${cur_date#* }
printf "%s-%s-%s %s\n" "$d" "${amn:$(((dm-1)*3)):3}" "$y" "$t"

"dateformat.sh" 10 lines, 278 characters

DEV> dateformat.sh 
Processing date: 2013/03/13 13:24:50
./dateformat.sh[6]: m=${cur_date:5:2}: bad substitution

DEV> dateformat.sh 2013/12/11 14:20:25
Processing date: 2013/12/11
./dateformat.sh[6]: m=${cur_date:5:2}: bad substitution

DEV>

DEV> vi dateformat1.sh
#!/bin/ksh
cur_date="${1:-2013/03/13 13:24:50}"
printf "Processing date: %s\n" "$cur_date"
set -A amn JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
IFS='/ '
set -- $cur_date
printf "%s-%s-%s %s\n" "$3" "${amn[10#$2-1]}" "$1" "$4"
DEV> dateformat1.sh 
Processing date: 2013/03/13 13:24:50
13-MAR-2013 13:24:50
DEV> dateformat1.sh '2013/12/11 14:20:25'
Processing date: 2013/12/11 14:20:25
11-DEC-2013 14:20:25

DEV>

#!/bin/bash
cur_date="${1:-2013/03/13 13:24:50}"
printf "Processing date: %s\n" "$cur_date"
amn=(JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC)
IFS='/ '
set -- $cur_date
printf "%s-%s-%s %s\n" "$3" "${amn[10#$2-1]}" "$1" "$4"

#!/bin/bash
function dateformat1()
{
  amn=(JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC)
  OIFS=$IFS
  IFS='/ '
  set -- $1
  IFS=$OIFS
  printf "%s-%s-%s %s\n" "$3" "${amn[10#$2-1]}" "$1" "$4"
}

dateformat1 "${1:-2013/03/13 13:24:50}"