Use style word to quote output names.  The word should
be one of the following:
- `literal'
 - Output names as-is; this is the same as the `-N' or
`--literal' option.
 - `shell'
 - Quote names for the shell if they contain shell metacharacters or would
cause ambiguous output.
 - `shell-always'
 - Quote names for the shell, even if they would normally not require quoting.
 - `c'
 - Quote names as for a C language string; this is the same as the
`-Q' or `--quote-name' option.
 - `escape'
 - Quote as with `c' except omit the surrounding double-quote
characters; this is the same as the `-b' or `--escape' option.
 - `clocale'
 - Quote as with `c' except use quotation marks appropriate for the
locale.
 - `locale'
 - Like `clocale', but quote `like this' instead of "like
this" in the default C locale.  This looks nicer on many displays.
 
You can specify the default value of the `--quoting-style' option
with the environment variable QUOTING_STYLE.  If that environment
variable is not set, the default value is `literal', but this
default may change to `shell' in a future version of this package.