Rio

Tested Software version 0.5.27 on Linux. The homepage URL of this terminal is https://rioterm.com/. Full results available at ucs-detect repository path data/rio.yaml.

Score Breakdown

Detailed breakdown of how scores are calculated for Rio:

#	Score Type	Raw Score	Final Scaled Score
1	WIDE	93.87%	92.4%
2	NARROW	99.77%	99.7%
3	ZWJ	100.00%	100.0%
4	LANG	99.59%	99.6%
5	VS16	100.00%	100.0%
6	VS15	89.24%	(excluded)
7	SRI	0.00%	0.0%
8	SFZ	0.00%	0.0%
9	RI	100.00%	100.0%
10	FEAT	66.67%	66.7%
11	Graphics	100%	100.0%
12	Resources	50.9%	50.9%

Score Comparison Plot:

The following plot shows how this terminal’s scores compare to all other terminals tested.

../_images/rio_scores_scaled.png — Scaled scores comparison across all metrics (normalized 0-100%)

Final Scaled Score Calculation:

Raw Final Score: 86.93% (weighted average: WIDE + NARROW + ZWJ + LANG + VS16 + 0.33 * SRI + 0.33 * SFZ + RI + CAP + 0.5 * GFX) the categorized ‘average’ absolute support level of this terminal.

Note

RSC (Resources) is a composite CPU, memory, and runtime score, displayed for comparison but excluded from the final score FEAT (Features) is the fraction of notable features supported. GFX (Graphics) scores 100% for modern protocols (iTerm2, Kitty), 50% for legacy only (Sixel, ReGIS), 0% for none.
Final Scaled Score: 78.4% (normalized across all terminals tested). Final Scaled scores are normalized (0-100%) relative to all terminals tested

WIDE Score Details:

Wide character support calculation:

Total successful contested codepoints: 475
Total contested codepoints tested: 506
Formula: 475 / 506
Result: 93.87%

NARROW Score Details:

Narrow character support calculation:

Total successful contested codepoints: 5582
Total contested codepoints tested: 5595
Formula: 5582 / 5595
Result: 99.77%

ZWJ Score Details:

Emoji ZWJ (Zero-Width Joiner) support calculation:

Total successful sequences: 1445
Total sequences tested: 1445
Formula: 1445 / 1445
Result: 100.00%

VS16 Score Details:

Variation Selector-16 support calculation:

Errors: 0 of 426 codepoints tested
Success rate: 100.0%
Formula: 100.0 / 100
Result: 100.00%

Variation Selector-15 support:

Note

Interpretation of VS-15 is contested. Its width behavior is not consistently implemented across terminals; this measurement is informational and excluded from final scoring.

Variation Selector-15 support calculation:

Errors: 17 of 158 codepoints tested
Success rate: 89.2%
Formula: 89.2 / 100
Result: 89.24%

SRI Score Details:

Standalone Regional Indicator support calculation:

Total successful codepoints: 0
Total codepoints tested: 26
Formula: 0 / 26
Result: 0.00%

SFZ Score Details:

Standalone Fitzpatrick skin tone modifier support calculation:

Total successful codepoints: 0
Total codepoints tested: 5
Formula: 0 / 5
Result: 0.00%

RI Score Details:

Regional Indicator flag sequence support calculation:

Total successful sequences: 262
Total sequences tested: 262
Formula: 262 / 262
Result: 100.00%

Features Score Details:

Notable terminal features (12.0 / 18):

Set bracketed paste mode (2004): yes
Synchronized Output (2026): yes
In-Band Window Resize Notifications (2048): no
Send FocusIn/FocusOut events (1004): yes
Enable SGR Mouse Mode (1006): yes
Grapheme Clustering (2027): yes
Bracketed Paste MIME (5522): no
Kitty Keyboard (Full): yes
XTGETTCAP (Full): yes
Text Sizing (OSC 66): no
Tofu Detection: yes
Kitty Clipboard Protocol: no
OSC 52 Clipboard: yes
Kitty Pointer Shapes (OSC 22): no
Kitty Notifications (OSC 99): no
Color Report (OSC 10/11): yes
Terminal Identification (XTVERSION): yes
Truecolor Detection: yes

Raw score: 66.67%

Graphics Score Details:

Graphics protocol support (100%):

Sixel: yes
ReGIS: no
iTerm2: yes
Kitty: yes

Scoring: 100% for modern (iTerm2/Kitty), 50% for legacy only (Sixel/ReGIS), 0% for none

Resource Score Details:

Duration: 40.4s
Mean CPU: 47.2%
Mean RSS: 109.7 MB
Resources Score: 51/100
Note: log-scale composite cost = log(CPU+1) + log(RSS+1) + log(time+1)
Scaled result: 50.9%

LANG Score Details (Geometric Mean):

Geometric mean calculation:

Formula: (p₁ × p₂ × … × pₙ)^(1/n) where n = 85 contested languages
About geometric mean
Result: 99.59%

Wide character support

Wide character support of Rio is 97.7% (1007 errors of 44568 codepoints tested).

Sequence of a WIDE character, from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+00018FF7	‘\U00018ff7’	Cn	2	na

Total codepoints: 1

Shell test using printf(1), '|' should align in output:
```
$ printf "\xf0\x98\xbf\xb7|\\n12|\\n"
𘿷|
12|
```

Screenshot:

python wcwidth.wcswidth() measures width 2, while Rio measures width 1.

Narrow character support

Narrow character support of Rio is 100.0% (13 errors of 36254 codepoints tested).

Sequence of a NARROW character, from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+06DD	‘\u06dd’	Cf	1	ARABIC END OF AYAH

Total codepoints: 1

Shell test using printf(1), '|' should align in output:
```
$ printf "\xdb\x9d|\\n1|\\n"
۝|
1|
```
python wcwidth.wcswidth() measures width 1, while Rio measures width 0.

Emoji ZWJ support

Compatibility of Rio with the Unicode Emoji ZWJ sequence table is 100.0% (0 errors of 1445 sequences tested).

Variation Selector-16 support

Emoji VS-16 results for Rio is 0 errors out of 426 total codepoints tested, 100.0% success. All codepoint combinations with Variation Selector-16 tested were successful.

Variation Selector-15 support

Emoji VS-15 results for Rio is 17 errors out of 158 total codepoints tested, 89.2% success. Sequence of a WIDE Emoji made NARROW by Variation Selector-15, from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+274C	‘\u274c’	So	2	CROSS MARK
2	U+FE0E	‘\ufe0e’	Mn	0	VARIATION SELECTOR-15

Total codepoints: 2

Shell test using printf(1), '|' should align in output:

$ printf "\xe2\x9d\x8c\xef\xb8\x8e|\\n1|\\n"
❌︎|
1|

Screenshot:

python wcwidth.wcswidth() measures width 1, while Rio measures width 2.

Standalone Regional Indicator support

Standalone Regional Indicator support of Rio is 0.0% (26 errors of 26 codepoints tested).

Sequence of a standalone Regional Indicator, from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+0001F1F3	‘\U0001f1f3’	So	2	REGIONAL INDICATOR SYMBOL LETTER N

Total codepoints: 1

Shell test using printf(1), '|' should align in output:
```
$ printf "\xf0\x9f\x87\xb3|\\n12|\\n"
🇳|
12|
```

Screenshot:

python wcwidth.wcswidth() measures width 2, while Rio measures width 1.

Standalone Fitzpatrick modifier support

Standalone Fitzpatrick skin tone modifier support of Rio is 0.0% (5 errors of 5 codepoints tested).

Sequence of a standalone Fitzpatrick modifier, from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+0001F3FD	‘\U0001f3fd’	Sk	2	EMOJI MODIFIER FITZPATRICK TYPE-4

Total codepoints: 1

Shell test using printf(1), '|' should align in output:
```
$ printf "\xf0\x9f\x8f\xbd|\\n12|\\n"
🏽|
12|
```

Screenshot:

python wcwidth.wcswidth() measures width 2, while Rio measures width 1.

Regional Indicator flag sequence support

Regional Indicator flag sequence support of Rio is 100.0% (0 errors of 262 sequences tested).

Graphics Protocol Support

Rio supports the following graphics protocols: Sixel, iTerm2 inline images, Kitty graphics.

Detection Methods:

Sixel and ReGIS: Sixel: Detected; ReGIS: Not detected via the Device Attributes (DA1) query CSI c (\x1b[c). Sixel indicator (4): present, ReGIS indicator (3): not present.
Kitty graphics: Detected by sending a Kitty graphics query and checking for an OK response.
iTerm2 inline images: Detected by drawing a 1x1 transparent image, OSC 1337 ; File=inline=1, and checking that the cursor advanced a single column.
iTerm2 capabilities: Not detected via the OSC 1337 ; Capabilities query, which does not describe image support, and does not contribute to this score.

Device Attributes

Raw response: '\x1b[?62;4;6;22;52c'
Service class: 62 (VT520)

Detected Extensions:

Code

Description

4

Sixel graphics

6

Selective erase

22

ANSI color

52

OSC 52 clipboard

Language Support

The following 112 languages were tested with 100% success:

(Jinan), (Yeonbyeon), Aja, Amarakaeri, Arabic, Standard, Assyrian Neo-Aramaic, Baatonum, Bamun, Belanda Viri, Bengali, Bhojpuri, Bora, Burmese, Catalan (2), Chakma, Chickasaw, Chinantec, Chiltepec, Chinese, Gan, Chinese, Hakka, Chinese, Jinyu, Chinese, Mandarin (Beijing), Chinese, Mandarin (Guiyang), Chinese, Mandarin (Harbin), Chinese, Mandarin (Nanjing), Chinese, Mandarin (Simplified), Chinese, Mandarin (Tianjin), Chinese, Mandarin (Traditional), Chinese, Min Nan, Chinese, Wu, Chinese, Xiang, Chinese, Yue, Colorado, Dagaare, Southern, Dangme, Dari, Dendi, Dinka, Northeastern, Ditammari, Dzongkha, Evenki, Farsi, Western, Fon, French (Welche), Fur, Ga, Gen, Gilyak, Gujarati, Gumuz, Hindi, Japanese, Japanese (Osaka), Japanese (Tokyo), Kabyle, Kannada, Khmer, Central, Korean, Lamnso’, Lao, Lingala (tones), Magahi, Maithili, Maldivian, Maori (2), Marathi, Mazahua Central, Mirandese, Mixtec, Metlatónoc, Mon, Mongolian, Halh (Mongolian), Mòoré, Nanai, Navajo, Nepali, Nuosu, Orok, Otomi, Mezquital, Panjabi, Eastern, Panjabi, Western, Pashto, Northern, Picard, Pular (Adlam), Saint Lucian Creole French, Sanskrit, Secoya, Seraiki, Shan, Shipibo-Conibo, Sinhala, Siona, South Azerbaijani, Tagalog (Tagalog), Tai Dam, Tamang, Eastern, Tamazight, Central Atlas, Tamil, Tamil (Sri Lanka), Telugu, Tem, Thai, Thai (2), Tibetan, Central, Ticuna, Uduk, Veps, Vietnamese, Vietnamese (Han nom), Waama, Yaneshaʼ, Yiddish, Eastern, Yoruba, Éwé.

The following 6 languages are not fully supported:

lang	n_errors	n_total	pct_success
Khün	71	419	83.1%
Sanskrit (Grantha)	22	293	92.5%
Javanese (Javanese)	10	530	98.1%
Urdu (2)	1	82	98.8%
Urdu	1	110	99.1%
Malayalam	1	844	99.9%

Khün

Sequence of language Khün from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+1A20	‘\u1a20’	Lo	1	TAI THAM LETTER HIGH KA
2	U+1A6E	‘\u1a6e’	Mc	0	TAI THAM VOWEL SIGN E
3	U+1A60	‘\u1a60’	Mn	0	TAI THAM SIGN SAKOT
4	U+1A2F	‘\u1a2f’	Lo	1	TAI THAM LETTER DA
5	U+1A68	‘\u1a68’	Mn	0	TAI THAM VOWEL SIGN UUE

Total codepoints: 5

Shell test using printf(1), '|' should align in output:

$ printf "\xe1\xa8\xa0\xe1\xa9\xae\xe1\xa9\xa0\xe1\xa8\xaf\xe1\xa9\xa8|\\n12|\\n"
ᨠᩮ᩠ᨯᩨ|
12|

Screenshot:

python wcwidth.wcswidth() measures width 2, while Rio measures width 3.

Sanskrit (Grantha)

Sequence of language Sanskrit (Grantha) from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+00011315	‘\U00011315’	Lo	1	GRANTHA LETTER KA
2	U+0001134D	‘\U0001134d’	Mc	0	GRANTHA SIGN VIRAMA

Total codepoints: 2

Shell test using printf(1), '|' should align in output:

$ printf "\xf0\x91\x8c\x95\xf0\x91\x8d\x8d|\\n1|\\n"
𑌕𑍍|
1|

Screenshot:

python wcwidth.wcswidth() measures width 1, while Rio measures width 2.

Javanese (Javanese)

Sequence of language Javanese (Javanese) from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+A98F	‘\ua98f’	Lo	1	JAVANESE LETTER KA
2	U+A9C0	‘\ua9c0’	Mc	0	JAVANESE PANGKON

Total codepoints: 2

Shell test using printf(1), '|' should align in output:

$ printf "\xea\xa6\x8f\xea\xa7\x80|\\n1|\\n"
ꦏ꧀|
1|

Screenshot:

python wcwidth.wcswidth() measures width 1, while Rio measures width 2.

Urdu (2)

Sequence of language Urdu (2) from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+0601	‘\u0601’	Cf	1	ARABIC SIGN SANAH
2	U+06F1	‘\u06f1’	Nd	1	EXTENDED ARABIC-INDIC DIGIT ONE

Total codepoints: 2

Shell test using printf(1), '|' should align in output:
```
$ printf "\xd8\x81\xdb\xb1|\\n12|\\n"
؁۱|
12|
```

Screenshot:

Urdu

Sequence of language Urdu from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+0601	‘\u0601’	Cf	1	ARABIC SIGN SANAH
2	U+06F1	‘\u06f1’	Nd	1	EXTENDED ARABIC-INDIC DIGIT ONE

Total codepoints: 2

Shell test using printf(1), '|' should align in output:
```
$ printf "\xd8\x81\xdb\xb1|\\n12|\\n"
؁۱|
12|
```

Screenshot:

python wcwidth.wcswidth() measures width 2, while Rio measures width 1.

Malayalam

Sequence of language Malayalam from midpoint of alignment failure records:

#	Codepoint	Python	Category	wcwidth	Name
1	U+0D7B	‘\u0d7b’	Lo	1	MALAYALAM LETTER CHILLU N
2	U+0D4D	‘\u0d4d’	Mn	0	MALAYALAM SIGN VIRAMA
3	U+0D31	‘\u0d31’	Lo	1	MALAYALAM LETTER RRA
4	U+0D46	‘\u0d46’	Mc	0	MALAYALAM VOWEL SIGN E

Total codepoints: 4

Shell test using printf(1), '|' should align in output:

$ printf "\xe0\xb5\xbb\xe0\xb5\x8d\xe0\xb4\xb1\xe0\xb5\x86|\\n12|\\n"
ൻ്റെ|
12|

Screenshot:

python wcwidth.wcswidth() measures width 2, while Rio measures width 3.

DEC Private Modes Support

DEC private modes results for Rio: 5 changeable modes of 5 supported out of 8 total modes tested (62.5% support, 62.5% changeable).

Complete list of DEC private modes tested:

Mode	Name	Description	Supported	Changeable	Enabled
1004	FOCUS_IN_OUT_EVENTS	Send FocusIn/FocusOut events	Yes	Yes	No
1006	MOUSE_EXTENDED_SGR	Enable SGR Mouse Mode	Yes	Yes	No
2004	BRACKETED_PASTE	Set bracketed paste mode	Yes	Yes	No
2026	SYNCHRONIZED_OUTPUT	Synchronized Output	Yes	Yes	No
2027	GRAPHEME_CLUSTERING	Grapheme Clustering	Yes	Yes	Yes
2031	COLOR_PALETTE_UPDATES	Color palette updates	No	No	No
2048	IN_BAND_WINDOW_RESIZE	In-Band Window Resize Notifications	No	No	No
5522	BRACKETED_PASTE_MIME	Bracketed Paste MIME	No	No	No

Summary: 5 changeable, 3 not changeable.

Kitty Keyboard Protocol

Rio supports the Kitty keyboard protocol.

#	Flag	Key	Supported
1	Disambiguate escape codes	`disambiguate`	Yes
2	Report event types	`report_events`	Yes
3	Report alternate keys	`report_alternates`	Yes
4	Report all keys as escape codes	`report_all_keys`	Yes
5	Report associated text	`report_text`	Yes

Detection is performed by enabling all progressive enhancement modes by set (CSI = 31 ; 1 u) and re-querying with CSI ? u to confirm which modes the terminal honors, before restoring its original flags.

XTGETTCAP (Terminfo Capabilities)

Rio supports the XTGETTCAP sequence and reports 204 terminfo capabilities (Full).

#	Capability	Description	Value
1	AX	Supports default colors	(empty)
2	BD	Enter bold mode (kitty)	`\E[?2004l`
3	BE	Exit bold mode (kitty)	`\E[?2004h`
4	Cr	Set cursor color	`\E]112\a`
5	Cs	Reset cursor color	`\E]12;%p1%s\a`
6	E3	Erase scrollback	`\E[3J`
7	Ms	Clipboard set	`\E]52;%p1%s;%p2%s\a`
8	PE	Presentation end (kitty)	`\E[201~`
9	PS	Presentation start (kitty)	`\E[200~`
10	RGB	Bits per color channel (8 = 24-bit truecolor)	`8/8/8`
11	Se	Reset underline style	`\E[0 q`
12	Smulx	Styled underline	`\E[4:%p1%dm`
13	Ss	Set underline style	`\E[%p1%d q`
14	Sync	Synchronized output	`\EP=%p1%ds\E\`
15	TN	Terminal name	`rio`
16	XF	Extended functionality	(empty)
17	XT	Xterm extensions	(empty)
18	acsc	Alternate character set	``aaffggiijjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{\|\|}}~~
19	am	Auto right margin	(empty)
20	bce	Background color erase	(empty)
21	bel	Bell	`\a`
22	blink	Enter blink mode	`\E[5m`
23	bold	Enter bold mode	`\E[1m`
24	ccc	Can redefine colors	(empty)
25	civis	Hide cursor	`\E[?25l`
26	clear	Clear screen	`\E[H\E[2J`
27	cnorm	Normal cursor	`\E[?12l\E[?25h`
28	colors	Max colors on screen	`256`
29	cols	Columns	`80`
30	cr	Carriage return	`\r`
31	csr	Change scroll region	`\E[%i%p1%d;%p2%dr`
32	cub	Cursor left n	`\E[%p1%dD`
33	cub1	Cursor left	`\b`
34	cud	Cursor down n	`\E[%p1%dB`
35	cud1	Cursor down	`\n`
36	cuf	Cursor right n	`\E[%p1%dC`
37	cuf1	Cursor right	`\E[C`
38	cup	Cursor address	`\E[%i%p1%d;%p2%dH`
39	cuu	Cursor up n	`\E[%p1%dA`
40	cuu1	Cursor up	`\E[A`
41	cvvis	Very visible cursor	`\E[?12;25h`
42	dch	Delete n characters	`\E[%p1%dP`
43	dch1	Delete character	`\E[P`
44	dim	Enter dim mode	`\E[2m`
45	dl	Delete n lines	`\E[%p1%dM`
46	dl1	Delete line	`\E[M`
47	dsl	Disable status line	`\E]2;\a`
48	ech	Erase characters	`\E[%p1%dX`
49	ed	Clear to end of screen	`\E[J`
50	el	Clear to end of line	`\E[K`
51	el1	Clear to start of line	`\E[1K`
52	flash	Flash screen	`\E[?5h$<100/>\E[?5l`
53	fsl	From status line	`\a`
54	home	Cursor home	`\E[H`
55	hpa	Horizontal position	`\E[%i%p1%dG`
56	hs	Has status line	(empty)
57	ht	Horizontal tab	`\t`
58	hts	Set tab stop	`\EH`
59	ich	Insert n characters	`\E[%p1%d@`
60	il	Insert n lines	`\E[%p1%dL`
61	il1	Insert line	`\E[L`
62	ind	Scroll forward	`\n`
63	indn	Scroll forward n	`\E[%p1%dS`
64	initc	Initialize color	`\E]4;%p1%d;rgb:%p2%{255}%%{1000}%/%2.2X/%p3%{255}%%{100...`
65	invis	Invisible cursor	`\E[8m`
66	is2	Init 2 string	`\E[!p\E[?3;4l\E[4l\E>`
67	it	Init tabs	`8`
68	kDC	Shifted delete-char key	`\E[3;2~`
69	kDC3	Alt delete-char key	`\E[3;3~`
70	kDC4	Alt-Shift delete-char key	`\E[3;4~`
71	kDC5	Ctrl delete-char key	`\E[3;5~`
72	kDC6	Ctrl-Shift delete-char key	`\E[3;6~`
73	kDC7	Ctrl-Alt delete-char key	`\E[3;7~`
74	kDN	Shifted down-arrow key	`\E[1;2B`
75	kDN3	Alt down-arrow key	`\E[1;3B`
76	kDN4	Alt-Shift down-arrow key	`\E[1;4B`
77	kDN5	Ctrl down-arrow key	`\E[1;5B`
78	kDN6	Ctrl-Shift down-arrow key	`\E[1;6B`
79	kDN7	Ctrl-Alt down-arrow key	`\E[1;7B`
80	kEND	Shifted end key	`\E[1;2F`
81	kEND3	Alt end key	`\E[1;3F`
82	kEND4	Alt-Shift end key	`\E[1;4F`
83	kEND5	Ctrl end key	`\E[1;5F`
84	kEND6	Ctrl-Shift end key	`\E[1;6F`
85	kEND7	Ctrl-Alt end key	`\E[1;7F`
86	kHOM	Shifted home key	`\E[1;2H`
87	kHOM3	Alt home key	`\E[1;3H`
88	kHOM4	Alt-Shift home key	`\E[1;4H`
89	kHOM5	Ctrl home key	`\E[1;5H`
90	kHOM6	Ctrl-Shift home key	`\E[1;6H`
91	kHOM7	Ctrl-Alt home key	`\E[1;7H`
92	kIC	Shifted insert-char key	`\E[2;2~`
93	kIC3	Alt insert-char key	`\E[2;3~`
94	kIC4	Alt-Shift insert-char key	`\E[2;4~`
95	kIC5	Ctrl insert-char key	`\E[2;5~`
96	kIC6	Ctrl-Shift insert-char key	`\E[2;6~`
97	kIC7	Ctrl-Alt insert-char key	`\E[2;7~`
98	kLFT	Shifted left-arrow key	`\E[1;2D`
99	kLFT3	Alt left-arrow key	`\E[1;3D`
100	kLFT4	Alt-Shift left-arrow key	`\E[1;4D`
101	kLFT5	Ctrl left-arrow key	`\E[1;5D`
102	kLFT6	Ctrl-Shift left-arrow key	`\E[1;6D`
103	kLFT7	Ctrl-Alt left-arrow key	`\E[1;7D`
104	kNXT	Shifted next-page key	`\E[6;2~`
105	kNXT3	Alt next-page key	`\E[6;3~`
106	kNXT4	Alt-Shift next-page key	`\E[6;4~`
107	kNXT5	Ctrl next-page key	`\E[6;5~`
108	kNXT6	Ctrl-Shift next-page key	`\E[6;6~`
109	kNXT7	Ctrl-Alt next-page key	`\E[6;7~`
110	kPRV	Shifted previous-page key	`\E[5;2~`
111	kPRV3	Alt previous-page key	`\E[5;3~`
112	kPRV4	Alt-Shift previous-page key	`\E[5;4~`
113	kPRV5	Ctrl previous-page key	`\E[5;5~`
114	kPRV6	Ctrl-Shift previous-page key	`\E[5;6~`
115	kPRV7	Ctrl-Alt previous-page key	`\E[5;7~`
116	kRIT	Shifted right-arrow key	`\E[1;2C`
117	kRIT3	Alt right-arrow key	`\E[1;3C`
118	kRIT4	Alt-Shift right-arrow key	`\E[1;4C`
119	kRIT5	Ctrl right-arrow key	`\E[1;5C`
120	kRIT6	Ctrl-Shift right-arrow key	`\E[1;6C`
121	kRIT7	Ctrl-Alt right-arrow key	`\E[1;7C`
122	kUP	Shifted up-arrow key	`\E[1;2A`
123	kUP3	Alt up-arrow key	`\E[1;3A`
124	kUP4	Alt-Shift up-arrow key	`\E[1;4A`
125	kUP5	Ctrl up-arrow key	`\E[1;5A`
126	kUP6	Ctrl-Shift up-arrow key	`\E[1;6A`
127	kUP7	Ctrl-Alt up-arrow key	`\E[1;7A`
128	kb2	Keypad center	`\EOE`
129	kbs	Backspace key
130	kcbt	Back-tab key	`\E[Z`
131	kcub1	Left arrow key	`\EOD`
132	kcud1	Down arrow key	`\EOB`
133	kcuf1	Right arrow key	`\EOC`
134	kcuu1	Up arrow key	`\EOA`
135	kdch1	Delete character key	`\E[3~`
136	kend	End key	`\EOF`
137	kent	Enter/send key	`\EOM`
138	kf1	Function key F1	`\EOP`
139	kf10	Function key F10	`\E[21~`
140	kf11	Function key F11	`\E[23~`
141	kf12	Function key F12	`\E[24~`
142	kf2	Function key F2	`\EOQ`
143	kf3	Function key F3	`\EOR`
144	kf4	Function key F4	`\EOS`
145	kf5	Function key F5	`\E[15~`
146	kf6	Function key F6	`\E[17~`
147	kf7	Function key F7	`\E[18~`
148	kf8	Function key F8	`\E[19~`
149	kf9	Function key F9	`\E[20~`
150	khome	Home key	`\EOH`
151	kich1	Insert character key	`\E[2~`
152	kind	Scroll-down key	`\E[1;2B`
153	km	Has meta key	(empty)
154	kmous	Mouse key	`\E[M`
155	knp	Next page key	`\E[6~`
156	kpp	Previous page key	`\E[5~`
157	kri	Scroll-up key	`\E[1;2A`
158	kxIN	Keyboard in (kitty)	`\E[I`
159	kxOUT	Keyboard out (kitty)	`\E[O`
160	lines	Lines	`24`
161	mc5i	Will not echo input	(empty)
162	mir	Move in insert mode	(empty)
163	msgr	Move in standout mode	(empty)
164	npc	No pad character	(empty)
165	oc	Original colors	`\E]104\a`
166	op	Original pair	`\E[39;49m`
167	pairs	Max color pairs	`32767`
168	rc	Restore cursor	`\E8`
169	rep	Repeat character	`%p1%c\E[%p2%{1}%-%db`
170	rev	Enter reverse mode	`\E[7m`
171	ri	Reverse index	`\EM`
172	rin	Scroll reverse n	`\E[%p1%dT`
173	ritm	Exit italics mode	`\E[23m`
174	rmacs	Exit alternate charset mode	`\E(B`
175	rmam	Disable line wrap	`\E[?7l`
176	rmcup	Exit alt screen	`\E[?1049l\E[23;0;0t`
177	rmir	Exit insert mode	`\E[4l`
178	rmkx	Keypad local mode	`\E[?1l\E>`
179	rmm	Reset meta mode	`\E[?1034l`
180	rmso	Exit standout mode	`\E[27m`
181	rmul	Exit underline mode	`\E[24m`
182	rs1	Reset string 1	`\Ec\E]104\a`
183	rs2	Reset string 2	`\E[!p\E[?3;4l\E[4l\E>`
184	sc	Save cursor	`\E7`
185	setab	Set background color	`\E[%?%p1%{8}%<%t4%p1%d%e%p1%{16}%<%t10%p1%{8}%-%d%e48;5;%...`
186	setaf	Set foreground color	`\E[%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5;%p...`
187	sgr	Set attributes	`%?%p9%t\E(0%e\E(B%;\E[0%?%p6%t;1%;%?%p5%t;2%;%?%p2%t;4%;%...`
188	sgr0	Reset attributes	`\E(B\E[m`
189	sitm	Enter italics mode	`\E[3m`
190	smacs	Enter alternate charset mode	`\E(0`
191	smam	Enable line wrap	`\E[?7h`
192	smcup	Enter alt screen	`\E[?1049h\E[22;0;0t`
193	smir	Enter insert mode	`\E[4h`
194	smkx	Keypad transmit mode	`\E[?1h\E=`
195	smso	Enter standout mode	`\E[7m`
196	smul	Enter underline mode	`\E[4m`
197	tbc	Clear all tabs	`\E[3g`
198	tsl	To status line	`\E]2;`
199	u6	CPR response format	`\E[%i%d;%dR`
200	u7	CPR request	`\E[6n`
201	u8	DA response format	`\E[?%[;0123456789]c`
202	u9	DA request	`\E[c`
203	vpa	Vertical position	`\E[%i%p1%dd`
204	xenl	Newline glitch	(empty)

The XTGETTCAP sequence (DCS + q Pt ST) allows applications to query terminfo capabilities directly from the terminal emulator, rather than relying on the system terminfo database.

Text Sizing Protocol (OSC 66)

Rio does not support the Text Sizing protocol.

Tofu Detection

A tofu is the □ U+25A1 WHITE SQUARE placeholder box drawn in place of a codepoint the terminal’s font has no glyph for. Two protocols allow a program to ask which codepoints may ‘tofu’: mintty’s Font Glyph Coverage Enquiry and the Glyph Protocol implemented first by Rio.

Rio answers by the Glyph Protocol q verb, APC 25a1.

Protocol: glyph

Warning

Both protocols answer about single codepoints only. They are without support for grapheme clusters: ligatures, mark positioning, ZWJ joining, VS-15 and VS-16 presentation, contextual forms, etc.

What is measured below is a property of the font this terminal was configured with when tested, and not of the terminal emulator: it is reported, but is not scored. GNU’s Unifont is sometimes configured for use.

Every assigned codepoint of Unicode version 18.0.0 that occupies a cell of its own is tested, less the ideographic extension and historic script ranges that no general-purpose font is known to carry.

Tofus were detected for 0 out of 73,679 codepoints tested.

Note

These ranges are left out of the sweep, and of the count above: they are a tofu in all but a few specialist CJK and historic script fonts, and a font meant for terminal use is not worse for lacking them. They account for 94,515 of the 169,821 codepoints that could be tested; pass ucs-detect --include-uncommon-codepoints to sweep them as well.

U+16FF0..``U+18CFF`` — Ideographic Symbols and Punctuation, Khitan Small Script, Tangut, Tangut Components (7,393 codepoints)
U+18D00..``U+18DFF`` — Tangut Components Supplement, Tangut Supplement (148 codepoints)
U+1B000..``U+1B2FF`` — Kana Extended-A, Kana Supplement, Nushu, Small Kana Extension (703 codepoints)
U+20000..``U+2A6FF`` — CJK Unified Ideographs Extension B (42,720 codepoints)
U+2A700..``U+2B73F`` — CJK Unified Ideographs Extension C (4,160 codepoints)
U+2B740..``U+2B81F`` — CJK Unified Ideographs Extension D (223 codepoints)
U+2B820..``U+2CEAF`` — CJK Unified Ideographs Extension E (5,774 codepoints)
U+2CEB0..``U+2EBEF`` — CJK Unified Ideographs Extension F (7,473 codepoints)
U+2EBF0..``U+2F7FF`` — CJK Unified Ideographs Extension I (622 codepoints)
U+2F800..``U+2FFFF`` — CJK Compatibility Ideographs Supplement (542 codepoints)
U+30000..``U+3134F`` — CJK Unified Ideographs Extension G (4,939 codepoints)
U+31350..``U+323AF`` — CJK Unified Ideographs Extension H (4,192 codepoints)
U+323B0..``U+3FFFD`` — CJK Unified Ideographs Extension J, Seal (15,626 codepoints)

No Unicode block holds a tofu: every codepoint tested has a glyph.

Truecolor Support

Rio supports 24-bit truecolor, detectable via:

XTGETTCAP (RGB capability): yes (RGB)
DECRQSS (truecolor probe): no
COLORTERM: yes (truecolor)

OSC 52 Clipboard Support

Rio supports OSC 52 clipboard operations (detected via DA1 extension 52 + XTGETTCAP Ms).

DA1 extension 52: yes
XTGETTCAP Ms: yes

Terminal Identification

Rio is identified as Rio version 0.5.27 (detected via XTVERSION + XTGETTCAP TN).

XTVERSION (raw): Rio 0.5.27
XTVERSION: yes
XTGETTCAP TN: yes (rio)
ENQ: no
TERM_PROGRAM: yes (rio)
TERM: yes (rio)

Reproduction

To reproduce these results for Rio, install and run ucs-detect with the following commands:

uvx ucs-detect --rerun data/rio.yaml

Test Performance

The test suite completed in 40.39 seconds (40s).

Mean CPU: 47.2%
Mean RSS: 109.7 MB
Total time: 40.4s

CPU usage over time — CPU usage during test execution for *Rio*.

RSS memory over time — RSS memory usage during test execution for *Rio*.

Duration comparison — Test duration for *Rio* compared to all other terminals.

CPU % vs Duration — CPU % vs duration trade-off for *Rio*.