1This file is help.def, from which is created help.c. 2It implements the builtin "help" in Bash. 3 4Copyright (C) 1987-2003 Free Software Foundation, Inc. 5 6This file is part of GNU Bash, the Bourne Again SHell. 7 8Bash is free software; you can redistribute it and/or modify it under 9the terms of the GNU General Public License as published by the Free 10Software Foundation; either version 2, or (at your option) any later 11version. 12 13Bash is distributed in the hope that it will be useful, but WITHOUT ANY 14WARRANTY; without even the implied warranty of MERCHANTABILITY or 15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 16for more details. 17 18You should have received a copy of the GNU General Public License along 19with Bash; see the file COPYING. If not, write to the Free Software 20Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. 21 22$PRODUCES help.c 23 24$BUILTIN help 25$FUNCTION help_builtin 26$DEPENDS_ON HELP_BUILTIN 27$SHORT_DOC help [-s] [pattern ...] 28Display helpful information about builtin commands. If PATTERN is 29specified, gives detailed help on all commands matching PATTERN, 30otherwise a list of the builtins is printed. The -s option 31restricts the output for each builtin command matching PATTERN to 32a short usage synopsis. 33$END 34 35#include <config.h> 36 37#if defined (HELP_BUILTIN) 38#include <stdio.h> 39 40#if defined (HAVE_UNISTD_H) 41# ifdef _MINIX 42# include <sys/types.h> 43# endif 44# include <unistd.h> 45#endif 46 47#include <errno.h> 48 49#include <filecntl.h> 50 51#include "../bashintl.h" 52 53#include "../shell.h" 54#include "../builtins.h" 55#include "../pathexp.h" 56#include "common.h" 57#include "bashgetopt.h" 58 59#include <glob/strmatch.h> 60#include <glob/glob.h> 61 62#ifndef errno 63extern int errno; 64#endif 65 66static void show_builtin_command_help __P((void)); 67static void show_longdoc __P((int)); 68 69/* Print out a list of the known functions in the shell, and what they do. 70 If LIST is supplied, print out the list which matches for each pattern 71 specified. */ 72int 73help_builtin (list) 74 WORD_LIST *list; 75{ 76 register int i; 77 char *pattern, *name; 78 int plen, match_found, sflag; 79 80 sflag = 0; 81 reset_internal_getopt (); 82 while ((i = internal_getopt (list, "s")) != -1) 83 { 84 switch (i) 85 { 86 case 's': 87 sflag = 1; 88 break; 89 default: 90 builtin_usage (); 91 return (EX_USAGE); 92 } 93 } 94 list = loptend; 95 96 if (list == 0) 97 { 98 show_shell_version (0); 99 show_builtin_command_help (); 100 return (EXECUTION_SUCCESS); 101 } 102 103 /* We should consider making `help bash' do something. */ 104 105 if (glob_pattern_p (list->word->word)) 106 { 107 if (list->next) 108 printf (_("Shell commands matching keywords `")); 109 else 110 printf (_("Shell commands matching keyword `")); 111 print_word_list (list, ", "); 112 printf ("'\n\n"); 113 } 114 115 for (match_found = 0, pattern = ""; list; list = list->next) 116 { 117 pattern = list->word->word; 118 plen = strlen (pattern); 119 120 for (i = 0; name = shell_builtins[i].name; i++) 121 { 122 QUIT; 123 if ((strncmp (pattern, name, plen) == 0) || 124 (strmatch (pattern, name, FNMATCH_EXTFLAG) != FNM_NOMATCH)) 125 { 126 printf ("%s: %s\n", name, shell_builtins[i].short_doc); 127 128 if (sflag == 0) 129 show_longdoc (i); 130 131 match_found++; 132 } 133 } 134 } 135 136 if (match_found == 0) 137 { 138 builtin_error (_("no help topics match `%s'. Try `help help' or `man -k %s' or `info %s'."), pattern, pattern, pattern); 139 return (EXECUTION_FAILURE); 140 } 141 142 fflush (stdout); 143 return (EXECUTION_SUCCESS); 144} 145 146/* By convention, enforced by mkbuiltins.c, if separate help files are being 147 used, the long_doc array contains one string -- the full pathname of the 148 help file for this builtin. */ 149static void 150show_longdoc (i) 151 int i; 152{ 153 register int j; 154 char * const *doc; 155 int fd; 156 157 doc = shell_builtins[i].long_doc; 158 159 if (doc && doc[0] && *doc[0] == '/' && doc[1] == (char *)NULL) 160 { 161 fd = open (doc[0], O_RDONLY); 162 if (fd == -1) 163 { 164 builtin_error (_("%s: cannot open: %s"), doc[0], strerror (errno)); 165 return; 166 } 167 zcatfd (fd, 1, doc[0]); 168 close (fd); 169 } 170 else 171 for (j = 0; doc[j]; j++) 172 printf ("%*s%s\n", BASE_INDENT, " ", _(doc[j])); 173} 174 175static void 176show_builtin_command_help () 177{ 178 int i, j; 179 char blurb[36]; 180 181 printf ( 182_("These shell commands are defined internally. Type `help' to see this list.\n\ 183Type `help name' to find out more about the function `name'.\n\ 184Use `info bash' to find out more about the shell in general.\n\ 185Use `man -k' or `info' to find out more about commands not in this list.\n\ 186\n\ 187A star (*) next to a name means that the command is disabled.\n\ 188\n")); 189 190 for (i = 0; i < num_shell_builtins; i++) 191 { 192 QUIT; 193 blurb[0] = (shell_builtins[i].flags & BUILTIN_ENABLED) ? ' ' : '*'; 194 strncpy (blurb + 1, shell_builtins[i].short_doc, 34); 195 blurb[35] = '\0'; 196 printf ("%s", blurb); 197 198 if (i % 2) 199 printf ("\n"); 200 else 201 for (j = strlen (blurb); j < 35; j++) 202 putc (' ', stdout); 203 } 204 if (i % 2) 205 printf ("\n"); 206} 207#endif /* HELP_BUILTIN */ 208