Add double quotes to prevent globbing and word splitting

[naltun]

What globbing is (from TLDP):

Bash itself cannot recognize Regular Expressions. Inside scripts, it is commands and utilities -- such as sed and awk -- that interpret RE's.

Bash does carry out filename expansion [1] -- a process known as globbing -- but this does not use the standard RE set. Instead, globbing recognizes and expands wild cards. Globbing interprets the standard wild card characters [2] -- * and ?, character lists in square brackets, and certain other special characters (such as ^ for negating the sense of a match). There are important limitations on wild card characters in globbing, however. Strings containing * will not match filenames that start with a dot, as, for example, .bashrc. [3] Likewise, the ? has a different meaning in globbing than as part of an RE.

Regarding word splitting (also from TLDP):

When referencing a variable, it is generally advisable to enclose its name in double quotes. This prevents reinterpretation of all special characters within the quoted string.

I have added doubles quotes in order to prevent globbing and word splitting.