UNIX for Dummies Questions & Answers

10110RAMAS90890
10111GURUS88990
10112SHEEP10110
10113SRIKA10110

[ctsgnb@shell ~]$ cat infile
10110RAMAS90890
10111GURUS88990
10112SHEEP10110
10113SRIKA10110
[ctsgnb@shell ~]$ empid=10110
[ctsgnb@shell ~]$ grep ^$empid infile
10110RAMAS90890
[ctsgnb@shell ~]$ grep -E ^.{10}$empid infile
10112SHEEP10110
10113SRIKA10110
[ctsgnb@shell ~]$

IND10110RAMAS90890
AUS10111GURUS88990
SRI10112SHEEP10110
ENG10113SRIKA10110

#!/bin/bash
if  [ $# -lt 3 ]
then
echo "Usage: ./empListQuery -FieldNo SearchString FileName"
else
field=$1
string=$2
file=$3
count=1
lines=`wc -l $file | cut -d ' ' -f 1`
while [ $count -le $lines ]
do
case $field in
    1)
        head -$count $file | tail -1 | cut -c 1-3 | grep  -q $string 
    if [ $? -eq 0 ]
then
     head -$count $file | tail -1
fi ;;
    2)
        head -$count $file | tail -1 | cut -c 4-8 | grep  -q $string 
    if [ $? -eq 0 ]
then
         head -$count $file | tail -1 
fi ;;
    3)
        head -$count $file | tail -1 | cut -c 9-13 | grep  -q $string 
    if [ $? -eq 0 ]
then
         head -$count $file | tail -1 
fi ;;

    4)
        head -$count $file | tail -1 | cut -c 14-18 | grep  -q $string 
    if [ $? -eq 0 ]
then
         head -$count $file | tail -1 
fi ;;

    *)
        echo "Please enter a number within 4 for firstArgument"
  esac
count=`expr $count + 1`
done
fi

[ctsgnb@shell ~]$ grep $empid infile
10110RAMAS90890
10112SHEEP10110
10113SRIKA10110
[ctsgnb@shell ~]$

cat <filename> | cut -c <start position>-<end-position> | grep -n "required data"

Head -<linenumber> filename | tail -1