我想将Unicode头骨和交叉骨头添加到我的shell提示符(特别是' skull and crossbones ' (U+2620)),但我不知道让echo吐出它的魔法咒语,或任何其他4位Unicode字符。两位数的数字很简单。例如echo -e "\x55",。

除了下面的答案之外,还应该注意到,很明显,您的终端需要支持Unicode以使输出符合您的期望。Gnome-terminal在这方面做得很好,但它在默认情况下不一定是打开的。

在macOS的终端应用程序中,选择首选项->编码,并选择Unicode (UTF-8)。


当前回答

这是一个完全内部的Bash实现,没有分叉,Unicode字符大小不限。

fast_chr() {
    local __octal
    local __char
    printf -v __octal '%03o' $1
    printf -v __char \\$__octal
    REPLY=$__char
}

function unichr {
    local c=$1    # Ordinal of char
    local l=0    # Byte ctr
    local o=63    # Ceiling
    local p=128    # Accum. bits
    local s=''    # Output string

    (( c < 0x80 )) && { fast_chr "$c"; echo -n "$REPLY"; return; }

    while (( c > o )); do
        fast_chr $(( t = 0x80 | c & 0x3f ))
        s="$REPLY$s"
        (( c >>= 6, l++, p += o+1, o>>=1 ))
    done

    fast_chr $(( t = p | c ))
    echo -n "$REPLY$s"
}

## test harness
for (( i=0x2500; i<0x2600; i++ )); do
    unichr $i
done

输出是:

─━│┃┄┅┆┇┈┉┊┋┌┍┎┏
┐┑┒┓└┕┖┗┘┙┚┛├┝┞┟
┠┡┢┣┤┥┦┧┨┩┪┫┬┭┮┯
┰┱┲┳┴┵┶┷┸┹┺┻┼┽┾┿
╀╁╂╃╄╅╆╇╈╉╊╋╌╍╎╏
═║╒╓╔╕╖╗╘╙╚╛╜╝╞╟
╠╡╢╣╤╥╦╧╨╩╪╫╬╭╮╯
╰╱╲╳╴╵╶╷╸╹╺╻╼╽╾╿
▀▁▂▃▄▅▆▇█▉▊▋▌▍▎▏
▐░▒▓▔▕▖▗▘▙▚▛▜▝▞▟
■□▢▣▤▥▦▧▨▩▪▫▬▭▮▯
▰▱▲△▴▵▶▷▸▹►▻▼▽▾▿
◀◁◂◃◄◅◆◇◈◉◊○◌◍◎●
◐◑◒◓◔◕◖◗◘◙◚◛◜◝◞◟
◠◡◢◣◤◥◦◧◨◩◪◫◬◭◮◯
◰◱◲◳◴◵◶◷◸◹◺◻◼◽◾◿

其他回答

只需在shell脚本中输入“☠”。在正确的地区和支持unicode的控制台上,它可以正常打印:

$ echo ☠
☠
$

一个丑陋的“变通方法”是输出UTF-8序列,但这也取决于所使用的编码:

$ echo -e '\xE2\x98\xA0'
☠
$

我用这个:

$ echo -e '\u2620'
☠

这比搜索十六进制表示法要简单得多。我在我的shell脚本中使用它。这适用于侏儒术语和urxvt AFAIK。

在bash中打印Unicode字符输出使用\x,\u或\u(第一个用于2位十六进制,第二个用于4位十六进制,第三个用于任何长度)

echo -e '\U1f602'

如果你想把它赋值给一个变量,使用$'…的语法

x=$'\U1f602'
echo $x

对不起,我又提了这个老问题。但是在使用bash时,有一种非常简单的方法可以从纯ASCII输入创建Unicode码点,甚至根本没有分叉:

unicode() { local -n a="$1"; local c; printf -vc '\\U%08x' "$2"; printf -va "$c"; }
unicodes() { local a c; for a; do printf -vc '\\U%08x' "$a"; printf "$c"; done; };

如下所示使用它来定义某些代码点

unicode crossbones 0x2620
echo "$crossbones"

或者将前65536个unicode码点转储到stdout(在我的机器上耗时不到2秒。额外的空格是为了防止某些字符由于shell的monospace字体而相互流入):

for a in {0..65535}; do unicodes "$a"; printf ' '; done

或者讲一个非常典型的父母的故事(这需要Unicode 2010):

unicodes 0x1F6BC 32 43 32 0x1F62D 32 32 43 32 0x1F37C 32 61 32 0x263A 32 32 43 32 0x1F4A9 10

解释:

printf '\UXXXXXXXX' prints out any Unicode character printf '\\U%08x' number prints \UXXXXXXXX with the number converted to Hex, this then is fed to another printf to actually print out the Unicode character printf recognizes octal (0oct), hex (0xHEX) and decimal (0 or numbers starting with 1 to 9) as numbers, so you can choose whichever representation fits best printf -v var .. gathers the output of printf into a variable, without fork (which tremendously speeds up things) local variable is there to not pollute the global namespace local -n var=other aliases var to other, such that assignment to var alters other. One interesting part here is, that var is part of the local namespace, while other is part of the global namespace. Please note that there is no such thing as local or global namespace in bash. Variables are kept in the environment, and such are always global. Local just puts away the current value and restores it when the function is left again. Other functions called from within the function with local will still see the "local" value. This is a fundamentally different concept than all the normal scoping rules found in other languages (and what bash does is very powerful but can lead to errors if you are a programmer who is not aware of that).

在UTF-8中,它实际上是6个数字(或3个字节)。

$ printf '\xE2\x98\xA0'
☠

要检查它是如何被控制台编码的,使用hexdump:

$ printf ☠ | hexdump
0000000 98e2 00a0                              
0000003