To change file permissions for all the files in a directory
$ chmod 755 *
To copy the file having spaces in its file name
EX: 1)Filename is Supplier Key Contacts.xls
Here there are spaces between file name.cp "Supplier Key Contacts.xls" "Supplier Key Contacts.xls_bkp"
To find and replace a string in one or more files in a directory
perl -pi -e 's/old_string/new_string/g' file_patternEX:- perl -pi -e 's/18791/7001/g' *.sh