editline.3 (5328B)
1 .TH EDITLINE 3 2 .SH NAME 3 editline \- command-line editing library with history 4 .SH SYNOPSIS 5 .nf 6 .B "char *" 7 .B "readline(prompt)" 8 .B " char *prompt;" 9 10 .B "void" 11 .B "add_history(line)" 12 .B " char *line;" 13 .fi 14 .SH DESCRIPTION 15 .I Editline 16 is a library that provides an line-editing interface with text recall. 17 It is intended to be compatible with the 18 .I readline 19 library provided by the Free Software Foundation, but much smaller. 20 The bulk of this manual page describes the user interface. 21 .PP 22 The 23 .I readline 24 routine returns a line of text with the trailing newline removed. 25 The data is returned in a buffer allocated with 26 .IR malloc (3), 27 so the space should be released with 28 .IR free (3) 29 when the calling program is done with it. 30 Before accepting input from the user, the specified 31 .I prompt 32 is displayed on the terminal. 33 .PP 34 The 35 .I add_history 36 routine makes a copy of the specified 37 .I line 38 and adds it to the internal history list. 39 .SS "User Interface" 40 A program that uses this library provides a simple emacs-like editing 41 interface to its users. 42 A line may be edited before it is sent to the calling program by typing either 43 control characters or escape sequences. 44 A control character, shown as a caret followed by a letter, is typed by 45 holding down the ``control'' key while the letter is typed. 46 For example, ``^A'' is a control-A. 47 An escape sequence is entered by typing the ``escape'' key followed by one or 48 more characters. 49 The escape key is abbreviated as ``ESC.'' 50 Note that unlike control keys, case matters in escape sequences; ``ESC\ F'' 51 is not the same as ``ESC\ f''. 52 .PP 53 An editing command may be typed anywhere on the line, not just at the 54 beginning. 55 In addition, a return may also be typed anywhere on the line, not just at 56 the end. 57 .PP 58 Most editing commands may be given a repeat count, 59 .IR n , 60 where 61 .I n 62 is a number. 63 To enter a repeat count, type the escape key, the number, and then 64 the command to execute. 65 For example, ``ESC\ 4\ ^f'' moves forward four characters. 66 If a command may be given a repeat count then the text ``[n]'' is given at the 67 end of its description. 68 .PP 69 The following control characters are accepted: 70 .RS 71 .nf 72 .ta \w'ESC DEL 'u 73 ^A Move to the beginning of the line 74 ^B Move left (backwards) [n] 75 ^D Delete character [n] 76 ^E Move to end of line 77 ^F Move right (forwards) [n] 78 ^G Ring the bell 79 ^H Delete character before cursor (backspace key) [n] 80 ^I Complete filename (tab key); see below 81 ^J Done with line (return key) 82 ^K Kill to end of line (or column [n]) 83 ^L Redisplay line 84 ^M Done with line (alternate return key) 85 ^N Get next line from history [n] 86 ^P Get previous line from history [n] 87 ^R Search backward (forward if [n]) through history for text; 88 \& must start line if text begins with an uparrow 89 ^T Transpose characters 90 ^V Insert next character, even if it is an edit command 91 ^W Wipe to the mark 92 ^X^X Exchange current location and mark 93 ^Y Yank back last killed text 94 ^[ Start an escape sequence (escape key) 95 ^]c Move forward to next character ``c'' 96 ^? Delete character before cursor (delete key) [n] 97 .fi 98 .RE 99 .PP 100 The following escape sequences are provided. 101 .RS 102 .nf 103 .ta \w'ESC DEL 'u 104 ESC\ ^H Delete previous word (backspace key) [n] 105 ESC\ DEL Delete previous word (delete key) [n] 106 ESC\ SP Set the mark (space key); see ^X^X and ^Y above 107 ESC\ \. Get the last (or [n]'th) word from previous line 108 ESC\ \? Show possible completions; see below 109 ESC\ < Move to start of history 110 ESC\ > Move to end of history 111 ESC\ b Move backward a word [n] 112 ESC\ d Delete word under cursor [n] 113 ESC\ f Move forward a word [n] 114 ESC\ l Make word lowercase [n] 115 ESC\ m Toggle if 8bit chars display normally or with ``M\-'' prefix 116 ESC\ u Make word uppercase [n] 117 ESC\ y Yank back last killed text 118 ESC\ v Show library version 119 ESC\ w Make area up to mark yankable 120 ESC\ nn Set repeat count to the number nn 121 ESC\ C Read from environment variable ``_C_'', where C is 122 \& an uppercase letter 123 .fi 124 .RE 125 .PP 126 The 127 .I editline 128 library has a small macro facility. 129 If you type the escape key followed by an uppercase letter, 130 .IR C , 131 then the contents of the environment variable 132 .I _C_ 133 are read in as if you had typed them at the keyboard. 134 For example, if the variable 135 .I _L_ 136 contains the following: 137 .RS 138 ^A^Kecho '^V^[[H^V^[[2J'^M 139 .RE 140 Then typing ``ESC L'' will move to the beginning of the line, kill the 141 entire line, enter the echo command needed to clear the terminal (if your 142 terminal is like a VT-100), and send the line back to the shell. 143 .PP 144 The 145 .I editline 146 library also does filename completion. 147 Suppose the root directory has the following files in it: 148 .RS 149 .nf 150 .ta \w'core 'u 151 bin vmunix 152 core vmunix.old 153 .fi 154 .RE 155 If you type ``rm\ /v'' and then the tab key. 156 .I Editline 157 will then finish off as much of the name as possible by adding ``munix''. 158 Because the name is not unique, it will then beep. 159 If you type the escape key and a question mark, it will display the 160 two choices. 161 If you then type a period and a tab, the library will finish off the filename 162 for you: 163 .RS 164 .nf 165 .RI "rm /v[TAB]" munix .TAB old 166 .fi 167 .RE 168 The tab key is shown by ``[TAB]'' and the automatically-entered text 169 is shown in italics. 170 .SH "BUGS AND LIMITATIONS" 171 Cannot handle lines more than 80 columns. 172 .SH AUTHORS 173 Simmule R. Turner <uunet.uu.net!capitol!sysgo!simmy> 174 and Rich $alz <rsalz@osf.org>. 175 Original manual page by DaviD W. Sanderson <dws@ssec.wisc.edu>.