Thanks for your help aigles,
I found out a short way to do this from one of the resource.
ls -lrt | awk '$9 ~ /20051001/ , $9 ~ /20060331/' | awk '{print $9}'
Amazingly it is working fine for my requirement. I can able to find the files between the Start_Date and End_Date which is date stamped with the file names.
Start_Date='20051001'
End_Date='20060331'
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20050810.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20050819.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20050930.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20051001.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20051020.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20051119.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20051216.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20051219.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20060101.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20060230.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20060310.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20060420.rpt
col1 col2 col3 col4 col5 col6 col7 col8 ramp_20060430.rpt
above script extracting the filenames correctly as:
ramp_20051001.rpt
ramp_20051020.rpt
ramp_20051119.rpt
ramp_20051216.rpt
ramp_20051219.rpt
ramp_20060101.rpt
ramp_20060230.rpt
ramp_20060310.rpt
Can any one explain this command that how it is able to select between these two date ranges !!!!!!???????
My Sincere Thanks to all.
Ganapati.