Keyboards are idiosyncratic. It should be obvious how to type
ordinary ASCII characters, backspace, tab, escape, and newline.
In Plan 9, the key labeled Return or Enter generates a newline
(0x0A); if there is a key labeled Line Feed, it generates a carriage
return (0x0D); Plan 9 eschews CRLFs. All control
characters are typed in the usual way; in particular, control–J
is a line feed and control–M a carriage return. On the PC and some
other machines, the key labeled Caps Lock acts as an additional
The delete character (0x7F) may be generated by a different key,
one near the extreme upper right of the keyboard. On the Next
it is the key labeled * (not the asterisk above the 8). On the
SLC and Sparcstation 2, delete is labeled Num Lock (the key above
Backspace labeled Delete functions as an additional
backspace key). On the other keyboards, the key labeled Del or
Delete generates the delete character.
The view character (0x80), used by rio(1), acme(1), and sam(1),
causes windows to scroll forward. It is generally somewhere near
the lower right of the main key area. The scroll character is
generated by the VIEW key on the Gnot, the Alt Graph key on the
SLC, and the arrow key ↓ on the other terminals. As a
convenience for sloppy typists, some programs interpret → and ←
keys, which lie on either side of ↓, as view keys as well. The
arrow key ↑ scrolls backward.
Characters in Plan 9 are runes (see utf(6)). Any rune can be typed
using a compose key followed by several other keys. The compose
key is also generally near the lower right of the main key area:
the NUM PAD key on the Gnot, the Alternate key on the Next, the
Compose key on the SLC, the Option key on the
Magnum, and either Alt key on the PC. After typing the compose
key, type a capital X and exactly four hexadecimal characters
(digits and a to f) or a lower case x followed by up to 6 hexadecimal
characters. If the sequence is shorter than 6 hexadecimal characters,
the terminator will not appear in the output. There
are shorthands for many characters, comprising the compose key
followed by a two– or three–character sequence. There are several
rules guiding the design of the sequences, as illustrated by the
following examples. The full list is too long to repeat here,
but is contained in the file /lib/keyboard in a format
suitable for grep(1) or look(1).|
Note the difference between ß (ss) and µ (micron) and the Greek
β and μ.
A repeated symbol gives a variant of that symbol, e.g., ?? yields
ASCII digraphs for mathematical operators give the corresponding
operator, e.g., <= yields ≤.
Two letters give the corresponding ligature, e.g., AE yields Æ.
Mathematical and other symbols are given by abbreviations for
their names, e.g., pg yields ¶.
Chess pieces are given by a w or b followed by a letter for the
piece (k for king, q for queen, r for rook, n for knight, b for
bishop, or p for pawn), e.g., wk for a white king.
Greek letters are given by an asterisk followed by a corresponding
latin letter, e.g., *d yields δ.
Cyrillic letters are given by an at sign followed by a corresponding
latin letter or letters, e.g., @ya yields я.
Script letters are given by a dollar sign followed by the corresponding
regular letter, e.g., $F yields ℱ.
A digraph of a symbol followed by a letter gives the letter with
an accent that looks like the symbol, e.g., ,c yields ç.
Two digits give the fraction with that numerator and denominator,
e.g., 12 yields ½.
The letter s followed by a character gives that character as a
superscript, e.g., s1 yields ¹.
Sometimes a pair of characters give a symbol related to the superimposition
of the characters, e.g., cO yields ©.
A mnemonic letter followed by $ gives a currency symbol, e.g.,
l$ yields £.