awk -f describe.awk schedule.def

describe.awk:
BEGIN {
#       printf("\ndescribe %s\n\n", title);
        printf("   %-15s %-8s %3s %3s %-4s\n", "Name", "Type", "Len", "Wth", "Null");
        printf("   %-15s %-8s %3s %3s %-4s\n", "---------------", "--------", "---", "---", "----");
}
# Excluding comment lines, (starting w/#):
/^[^#]/ {
        FS=",";
        printf("   %-15s %-8s %3s %3s %-4s\n", $1, $2, $3, $4, $5);
}
END { print ""; }

schedule.def:
# schedule.def
# name,type,length,width,null
Job,number,04,04,no
Vendor,varchar,50,10,no
DataType,varchar,20,15,no
Src,varchar,25,20,no
EDCPtcl,varchar,25,08,no
Ptcl,varchar,10,08,no
Dest,varchar,15,08,no
Process,varchar,01,07,no
Status,varchar,01,06,yes
TransferDt,date,07,15,no

output:
   Name            Type     Len Wth Null
   --------------- -------- --- --- ----
   Job,number,04,04,no                      
   Vendor          varchar   50  10 no  
   DataType        varchar   20  15 no  
   Src             varchar   25  20 no  
   EDCPtcl         varchar   25  08 no  
   Ptcl            varchar   10  08 no  
   Dest            varchar   15  08 no  
   Process         varchar   01  07 no  
   Status          varchar   01  06 yes 
   TransferDt      date      07  15 no