Escaping File Names

In this library, user-specified names are used in file names. So a function to escape file names is required.

ASCII Characters

For ASCII characters, the following rules are used:

Code	Character	Allow in This Library	Usability in Windows	Usability in Ubuntu	Notes
00	(NUL)	×	×	×	C0 control.
01	(SOH)	×	×	×	C0 control.
02	(STX)	×	×	×	C0 control.
03	(ETX)	×	×	×	C0 control.
04	(EOT)	×	×	×	C0 control.
05	(ENQ)	×	×	×	C0 control.
06	(ACK)	×	×	×	C0 control.
07	(BEL)	×	×	×	C0 control.
08	(BS)	×	×	×	C0 control.
09	(HT)	×	×	×	C0 control.
0A	(LF)	×	×	×	C0 control.
0B	(VT)	×	×	×	C0 control.
0C	(FF)	×	×	×	C0 control.
0D	(CR)	×	×	×	C0 control.
0E	(SO)	×	×	×	C0 control.
0F	(SI)	×	×	×	C0 control.
10	(DLE)	×	×	×	C0 control.
11	(DC1)	×	×	×	C0 control.
12	(DC2)	×	×	×	C0 control.
13	(DC3)	×	×	×	C0 control.
14	(DC4)	×	×	×	C0 control.
15	(NAK)	×	×	×	C0 control.
16	(SYN)	×	×	×	C0 control.
17	(ETB)	×	×	×	C0 control.
18	(CAN)	×	×	×	C0 control.
19	(EM)	×	×	×	C0 control.
1A	(SUB)	×	×	×	C0 control.
1B	(ESC)	×	×	×	C0 control.
1C	(FS)	×	×	×	C0 control.
1D	(GS)	×	×	×	C0 control.
1E	(RS)	×	×	×	C0 control.
1F	(US)	×	×	×	C0 control.
20	(space)	×	○	△	Quotation is needed.
21	!	○	○	○
22	“	×	△	△	Used as quotation.
23	#	×	○	△	Used in comments.
24	$	×	○	△	Used in variables.
25	%	×	△	○	Used in variables.
26	&	×	○	△	Used in shell.
27	‘	×	○	△	Used as quotation.
28	(	×	○	△	Used in shell.
29	)	×	○	△	Used in shell.
2A	*	×	×	△	Prohibited in Windows and used in shell.
2B	+	○	○	○
2C	,	×	△	△	Used as separators in some command line tools.
2D	-	○	○	○
2E	.	×	△	△	Confused with separator of extensions.
2F	/	×	×	×	Used as path separator.
30	0	○	○	○
31	1	○	○	○
32	2	○	○	○
33	3	○	○	○
34	4	○	○	○
35	5	○	○	○
36	6	○	○	○
37	7	○	○	○
38	8	○	○	○
39	9	○	○	○
3A	:	×	×	○	Prohibited in Windows.
3B	;	×	○	△	Used in shell.
3C	<	×	×	△	Prohibited in Windows and used in shell.
3D	=	×	△	△	Used as separators in some command line tools.
3E	>	×	×	△	Prohibited in Windows and used in shell.
3F	?	×	×	○	Prohibited in Windows.
40	@	○	○	○
41	A	○	○	○
42	B	○	○	○
43	C	○	○	○
44	D	○	○	○
45	E	○	○	○
46	F	○	○	○
47	G	○	○	○
48	H	○	○	○
49	I	○	○	○
4A	J	○	○	○
4B	K	○	○	○
4C	L	○	○	○
4D	M	○	○	○
4E	N	○	○	○
4F	O	○	○	○
50	P	○	○	○
51	Q	○	○	○
52	R	○	○	○
53	S	○	○	○
54	T	○	○	○
55	U	○	○	○
56	V	○	○	○
57	W	○	○	○
58	X	○	○	○
59	Y	○	○	○
5A	Z	○	○	○
5B	[	×	○	△	Used in shell.
5C	\	×	×	×	Used as path separator.
5D	]	×	○	△	Used in shell.
5E	^	○	○	○
5F	_	○	○	○
60	`	×	○	△	Used as quotation.
61	a	○	○	○
62	b	○	○	○
63	c	○	○	○
64	d	○	○	○
65	e	○	○	○
66	f	○	○	○
67	g	○	○	○
68	h	○	○	○
69	i	○	○	○
6A	j	○	○	○
6B	k	○	○	○
6C	l	○	○	○
6D	m	○	○	○
6E	n	○	○	○
6F	o	○	○	○
70	p	○	○	○
71	q	○	○	○
72	r	○	○	○
73	s	○	○	○
74	t	○	○	○
75	u	○	○	○
76	v	○	○	○
77	w	○	○	○
78	x	○	○	○
79	y	○	○	○
7A	z	○	○	○
7B	{	○	○	○
7C	|	×	×	△	Prohibited in Windows and used in shell.
7D	}	○	○	○
7E	~	○	○	○
7F	(DEL)	×	×	×	Control character.

Symbol	Meaning
×	Not allowed.
△	Allowed, but some care is needed to use.
○	Allowed.

Remaining Unicode Characters

Remaining Unicode characters are always escaped.