Fun things to try:

To see some useful and lovely glyphs, try this:

ugrep face 
ugrep alchemical 
ugrep ornament
ugrep bullet
ugrep '(vine|bud)'
ugrep vai
ugrep heavy
ugrep drawing
ugrep combining

Plain text search is simple:

    $ ugrep heart
    ☙	U+2619	REVERSED ROTATED FLORAL HEART BULLET
    ❣	U+2763	HEAVY HEART EXCLAMATION MARK ORNAMENT
    ❤	U+2764	HEAVY BLACK HEART
    ⋮	[ ... truncated for brevity ... ]
    💞	U+1F49E REVOLVING HEARTS
    💟	U+1F49F HEART DECORATION
    😍	U+1F60D SMILING FACE WITH HEART-SHAPED EYES
    😻	U+1F63B	SMILING CAT FACE WITH HEART-SHAPED EYES

Paste in a single character to lookup its codepoint:

    $ ugrep ☺
    ☺       U+263A  WHITE SMILING FACE

Arguments on the command line have an implicit wildcard between them:

    $ ugrep right.*gle
    $ ugrep right gle       # Equivalent
    »	U+00BB	RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK
    ’	U+2019	RIGHT SINGLE QUOTATION MARK
    ∟	U+221F	RIGHT ANGLE
    ⊿	U+22BF	RIGHT TRIANGLE

You can use regular expressions for fancier searches:

    $ ugrep -w '(wo|hu)?m(a|e)ns?'
    ᛗ	U+16D7	RUNIC LETTER MANNAZ MAN M
    ⛀	U+26C0	WHITE DRAUGHTS MAN
    ⛂	U+26C2	BLACK DRAUGHTS MAN
    ⼈	U+2F08	KANGXI RADICAL MAN
    ⼥	U+2F25	KANGXI RADICAL WOMAN
    𝌂	U+1D302	DIGRAM FOR HUMAN EARTH
    𝌄	U+1D304	DIGRAM FOR EARTHLY HUMAN
    🕴	U+1F574	MAN IN BUSINESS SUIT LEVITATING
    🕺	U+1F57A	MAN DANCING
    🚹	U+1F6B9	MENS SYMBOL
    🚺	U+1F6BA	WOMENS SYMBOL
    🤰	U+1F930	PREGNANT WOMAN
    🤵	U+1F935	MAN IN TUXEDO
    
    $ ugrep ^x		    #  Regex anchors ^ and $ work
    ⊻	U+22BB	XOR
    ⌧	U+2327	X IN A RECTANGLE BOX (clear key)

Use the -w flag to search only for complete words:

    $ ugrep -w R	    # The letter R used as a word
    $ ugrep "\bR\b"	    # (regex equivalent)
    R	U+0052	LATIN CAPITAL LETTER R
    Ŗ	U+0156	LATIN CAPITAL LETTER R WITH CEDILLA
    ℛ	U+211B	SCRIPT CAPITAL R (Script r)
    ℜ	U+211C	BLACK-LETTER CAPITAL R (Black-letter r)
    ℝ	U+211D	DOUBLE-STRUCK CAPITAL R (Double-struck r)

Use -c to display info for each character in a string.

    $ ugrep -c "ᕕ( ᐛ )ᕗ"
    ᕕ   U+1555  CANADIAN SYLLABICS FI
    (   U+0028  LEFT PARENTHESIS (opening parenthesis)
        U+0020  SPACE
    ᐛ   U+141B  CANADIAN SYLLABICS NASKAPI WAA
        U+0020  SPACE
    )   U+0029  RIGHT PARENTHESIS (closing parenthesis)
    ᕗ   U+1557  CANADIAN SYLLABICS FO

Aliases (alternate names) are also searched:

    $ ugrep backslash
    \	U+005C	REVERSE SOLIDUS (backslash)

Use .. to browse through a range of Unicode characters:

    $ ugrep 26b3..b
    ⚳	U+26B3	CERES
    ⚴	U+26B4	PALLAS
    ⚵	U+26B5	JUNO
    ⚶	U+26B6	VESTA
    ⚷	U+26B7	CHIRON
    ⚸	U+26B8	BLACK MOON LILITH
    ⚹	U+26B9	SEXTILE
    ⚺	U+26BA	SEMISEXTILE
    ⚻	U+26BB	QUINCUNX

    $ ugrep 1f470..ff  |  less
    👰	U+1F470	BRIDE WITH VEIL
    👱	U+1F471	PERSON WITH BLOND HAIR
    👲	U+1F472	MAN WITH GUA PI MAO
    👳	U+1F473	MAN WITH TURBAN
    👴	U+1F474	OLDER MAN
    👵	U+1F475	OLDER WOMAN
    👶	U+1F476	BABY
    👷	U+1F477	CONSTRUCTION WORKER
    👸	U+1F478	PRINCESS
    👹	U+1F479	JAPANESE OGRE
    👺	U+1F47A	JAPANESE GOBLIN
    👻	U+1F47B	GHOST
    👼	U+1F47C	BABY ANGEL
    👽	U+1F47D	EXTRATERRESTRIAL ALIEN
    ⋮	[ ... truncated for brevity ... ]
    📼	U+1F4FC	VIDEOCASSETTE
    📽	U+1F4FD	FILM PROJECTOR
    📾	U+1F4FE	PORTABLE STEREO
    📿	U+1F4FF	PRAYER BEADS

Sometimes it's useful (or just fun) to page through the Unicode
table and see what characters are defined in a region. (`ugrep
2700..ff`) Ranges are convenient, but very slow. Use regular
expressions if you want speed. (`ugrep U+27..`)

Ranges can have an optional increment:

$ ugrep 0..ffff..1000
   �    U+0000  <control> (null)
   က    U+1000  MYANMAR LETTER KA
  [ ]   U+2000  EN QUAD
  [　]  U+3000  IDEOGRAPHIC SPACE
   䀀   U+4000  cups; small cups ( M: fàn, C: fan3 fan4 fan6 )
   倀   U+5000  bewildered; rash, wildly ( M: chāng, C: caang1 caang4 coeng1 zaang1, J: KURUU TAORERU, K: CHANG, V: trành )
   怀   U+6000  bosom, breast; carry in bosom ( M: huái, C: waai4 )
   瀀   U+7000  [CJK Unified Ideographs] ( M: yōu, J: ATSUI )
   耀   U+8000  shine, sparkle, dazzle; glory ( M: yào, C: jiu6, J: KAGAYAKU, K: YO )
   退   U+9000  step back, retreat, withdraw ( M: tuì, C: teoi3, J: SHIRIZOKU SHIRIZOKERU, K: THOY, V: thoái )
   ꀀ   U+A000  YI SYLLABLE IT
   뀀   U+B000  Block: [Hangul Syllables]
   쀀   U+C000  Block: [Hangul Syllables]
   퀀   U+D000  Block: [Hangul Syllables]
   �    U+E000  <Private Use, First>
       U+F000  Block: [Private Use Area]

• Tip: pipe long output to less and search for a code point by pressing /U\+A60F.

Use -l to list which installed fonts contain a certain glyph:

  ugrep -l swash amp

• Requires FontConfig. (Most GNU/Linux boxes should already be set).

• The requested character may also be displayed in each of the listed typefaces, but only if your terminal supports sixel graphics (e.g., xterm -ti vt340) and you have ImageMagick installed.

Use -L to scale up the font examples when listing fonts

ugrep -L4 fdfd
   ﷽    U+FDFD  ARABIC LIGATURE BISMILLAH AR-RAHMAN AR-RAHEEM
                  Aldhabi
                  Trutypewriter PolyglOTT
                  Unifont

• Note that increasing the glyph size also increased the text size. Not all terminals are capable of "double height" text. If yours shows two lines of the same text in the usual size, try using --never-double-text.

Copy whitespace from the terminal

    $ ugrep -w space
	  [ ]   U+0020  SPACE (SP)
	  [ ]   U+00A0  NO-BREAK SPACE (non-breaking space) (NBSP)
	  [ ]   U+1680  OGHAM SPACE MARK
	  [ ]   U+2002  EN SPACE
	  [ ]   U+2003  EM SPACE
	  [ ]   U+2004  THREE-PER-EM SPACE
	  [ ]   U+2005  FOUR-PER-EM SPACE
	  [ ]   U+2006  SIX-PER-EM SPACE
	  [ ]   U+2007  FIGURE SPACE
	  [ ]   U+2008  PUNCTUATION SPACE
	  [ ]   U+2009  THIN SPACE
	  [ ]   U+200A  HAIR SPACE

Whitespace characters are printed with square brackets around them to make it easy to highlight and copy them from the terminal. They will also be shown with a yellow background, if the terminal allows.

Determine if an alias is actually a correction

Ugrep shows the character name in all caps and aliases are usually lowercase in parentheses. Some aliases are treated differently. For aesthetic reasons, abbreviations are also shown in uppercase. For example:

� U+FEFF ZERO WIDTH NO-BREAK SPACE (byte order mark) (BOM) (ZWNBSP)

There are 31 characters in Unicode which have the wrong name in the UnicodeData.txt database. Unicode includes the correct name as an alias in NameAliases.txt. If that file exists on your system, then ugrep will show the correction in Title Case Letters and in red letters, if the terminal supports color text.

︘ U+FE18 PRESENTATION FORM FOR VERTICAL RIGHT WHITE LENTICULAR BRAKCET (Presentation Form For Vertical Right White Lenticular Bracket)

View CJK (Chinese-Japanese-Korean) characters

Unicode does not actually define most CJK characters, except indirectly via Unihan, which maps certain blocks of characters to other standards.

• Ugrep allows one to specify the code point or paste in an example character to look up.

    $ ugrep 𰻞
       𰻞   U+30EDE biangbiang noodles ( M: biáng )
  
    $ ugrep 8000
    耀  U+8000  shine, sparkle, dazzle; glory ( M: yào, C: jiu6, J: KAGAYAKU, K: YO )
  

  

View all characters defined by Unicode:

    $ ugrep .?  |  less
    ⋮	[ ... over 30,000 glyphs elided for brevity ... ]

• Want just Unicode glyphs without the description? Please use fonttable. It shows all defined Unicode characters by default.

Show all possible code points, even the ones not defined in Unicode:

	$ ugrep 0..10FFFF | less
    ⋮	[ ... over a million lines elided for brevity ... ]

☝ This is currently very slow due to the way ugrep is implemented. You likely want to use fonttable -u instead.

Example 1: Unicode code point

$ ugrep 8000
   耀   U+8000  shine, sparkle, dazzle; glory ( M: yào, C: jiu6, J: KAGAYAKU, K: YO )

The parenthesized text at the end shows the romanized pronunciation of the character in Mandarin (pinyin), Cantonese (jyutping), Japanese (Hepburn), and Korean (Yale).

Example 2: Using -c to see characters in a string

$ ugrep -c 「⿺辶⿳穴⿰月⿰⿲⿱幺長⿱言馬⿱幺長刂心」
   「   U+300C  LEFT CORNER BRACKET (opening corner bracket)
   ⿺   U+2FFA  IDEOGRAPHIC DESCRIPTION CHARACTER SURROUND FROM LOWER LEFT
   辶   U+8FB6  walk; walking; KangXi radical 162 ( M: chuò, J: SHINNYOU )
   ⿳   U+2FF3  IDEOGRAPHIC DESCRIPTION CHARACTER ABOVE TO MIDDLE AND BELOW
   穴   U+7A74  cave, den, hole; KangXi radical 116 ( M: xué, C: jyut6, J: ANA, K: HYEL, V: huyệt )
   ⿰   U+2FF0  IDEOGRAPHIC DESCRIPTION CHARACTER LEFT TO RIGHT
   月   U+6708  moon; month; KangXi radical 74 ( M: yuè, C: jyut6, J: TSUKI, K: WEL, V: nguyệt )
   ⿰   U+2FF0  IDEOGRAPHIC DESCRIPTION CHARACTER LEFT TO RIGHT
   ⿲   U+2FF2  IDEOGRAPHIC DESCRIPTION CHARACTER LEFT TO MIDDLE AND RIGHT
   ⿱   U+2FF1  IDEOGRAPHIC DESCRIPTION CHARACTER ABOVE TO BELOW
   幺   U+5E7A  one; tiny, small ( M: yāo, C: jiu1, J: CHIISAI, K: YO )
   長   U+9577  long; length; excel in; leader ( M: zhǎng, C: coeng4 zoeng2, J: NAGAI TAKERU OSA, K: CANG, V: trường )
   ⿱   U+2FF1  IDEOGRAPHIC DESCRIPTION CHARACTER ABOVE TO BELOW
   言   U+8A00  words, speech; speak, say ( M: yán, C: jin4, J: KOTO IU KOTOBA, K: EN UN, V: ngôn )
   馬   U+99AC  horse; surname; KangXi radical 187 ( M: mǎ, C: maa5, J: UMA, K: MA, V: mã )
   ⿱   U+2FF1  IDEOGRAPHIC DESCRIPTION CHARACTER ABOVE TO BELOW
   幺   U+5E7A  one; tiny, small ( M: yāo, C: jiu1, J: CHIISAI, K: YO )
   長   U+9577  long; length; excel in; leader ( M: zhǎng, C: coeng4 zoeng2, J: NAGAI TAKERU OSA, K: CANG, V: trường )
   刂   U+5202  knife; radical number 18 ( M: dāo, C: dou1, J: RITSUTOU, K: TO )
   心   U+5FC3  heart; mind, intelligence; soul ( M: xīn, C: sam1, J: KOKORO, K: SIM, V: tâm )
   」   U+300D  RIGHT CORNER BRACKET (closing corner bracket)

Note 1: A "definition" is not a translation

Unihan calls the English gloss the character's "definition", but that is meant in a very loose sense. CJK characters change meaning based upon the context they are used in. For example, most Chinese words are made of two characters, such as "蜂鳥", which means "hummingbird", but ugrep would shows it as:

$ ugrep -c 蜂鳥
   蜂   U+8702  bee, wasp, hornet ( M: fēng, C: fung1, J: HACHI, K: PONG, V: ong )
   鳥   U+9CE5  bird; KangXi radical 196 ( M: niǎo, C: niu5, J: TORI, K: CO, V: điểu )

Note 2: Not all characters have readings

Unihan refers to this supplemental information — both the English gloss and the romanizations — as "readings". Readings are meant to be helpful, but are not normative and are only available for some characters.

Example of CJK with no Mandarin

$ ugrep 2bac3
   𫫃   U+2BAC3 (Cant.) sarcastic interrogative ( C: e1 )

Example of CJK with no pronunciation

$ ugrep 20015
   𠀕   U+20015 Variant of U+4E99 亙

Example of CJK with no English definition

$ ugrep 20016
   𠀖   U+20016 [CJK Unified Ideographs Extension B] ( V: khạng )

Example of CJK with no readings whatsoever

$ ugrep 2abcd
   𪯍   U+2ABCD [CJK Unified Ideographs Extension C]

Note that ugrep currently prints just the name of the block the character is in [within square brackets] if it has no better way to identify the character.

This is a rewrite of b9's AWK ugrep into Python. While AWK makes more sense for what this program does (comparing fields based on regexps), a rewrite was necessary because GNU awk, while plenty powerful, uses \y for word edges instead of the standard \b. Gawk does this for backwards compatibility with historic AWK, but lacks a way to disable it for new scripts.

Switching to Python did have the benefit of allowing more powerful Perlesque regexes (not that anyone has requested that).

Why not use the unicodedata module?

I do not use Python's unicodedata module because it is woefully insufficient. It allows one to search by character name only by specifying it fully and exactly: unicodedata.lookup("ROTATED HEAVY BLACK HEART BULLET").