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Diffstat (limited to 'builtins/echo.def')
| -rw-r--r-- | builtins/echo.def | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/builtins/echo.def b/builtins/echo.def new file mode 100644 index 0000000..6792659 --- /dev/null +++ b/builtins/echo.def @@ -0,0 +1,183 @@ +This file is echo.def, from which is created echo.c. +It implements the builtin "echo" in Bash. + +Copyright (C) 1987-2002 Free Software Foundation, Inc. + +This file is part of GNU Bash, the Bourne Again SHell. + +Bash is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 2, or (at your option) any later +version. + +Bash is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +You should have received a copy of the GNU General Public License along +with Bash; see the file COPYING. If not, write to the Free Software +Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. + +$PRODUCES echo.c +#include <config.h> + +#if defined (HAVE_UNISTD_H) +# include <unistd.h> +#endif + +#include "../bashansi.h" + +#include <stdio.h> +#include "../shell.h" + +$BUILTIN echo +$FUNCTION echo_builtin +$DEPENDS_ON V9_ECHO +$SHORT_DOC echo [-neE] [arg ...] +Output the ARGs. If -n is specified, the trailing newline is +suppressed. If the -e option is given, interpretation of the +following backslash-escaped characters is turned on: + \a alert (bell) + \b backspace + \c suppress trailing newline + \E escape character + \f form feed + \n new line + \r carriage return + \t horizontal tab + \v vertical tab + \\ backslash + \num the character whose ASCII code is NUM (octal). + +You can explicitly turn off the interpretation of the above characters +with the -E option. +$END + +$BUILTIN echo +$FUNCTION echo_builtin +$DEPENDS_ON !V9_ECHO +$SHORT_DOC echo [-n] [arg ...] +Output the ARGs. If -n is specified, the trailing newline is suppressed. +$END + +#if defined (V9_ECHO) +# define VALID_ECHO_OPTIONS "neE" +#else /* !V9_ECHO */ +# define VALID_ECHO_OPTIONS "n" +#endif /* !V9_ECHO */ + +/* System V machines already have a /bin/sh with a v9 behaviour. We + give Bash the identical behaviour for these machines so that the + existing system shells won't barf. Regrettably, the SUS v2 has + standardized the Sys V echo behavior. This variable is external + so that we can have a `shopt' variable to control it at runtime. */ +#if defined (DEFAULT_ECHO_TO_XPG) || defined (STRICT_POSIX) +int xpg_echo = 1; +#else +int xpg_echo = 0; +#endif /* DEFAULT_ECHO_TO_XPG */ + +extern int posixly_correct; + +/* Print the words in LIST to standard output. If the first word is + `-n', then don't print a trailing newline. We also support the + echo syntax from Version 9 Unix systems. */ +int +echo_builtin (list) + WORD_LIST *list; +{ + int display_return, do_v9, i, len; + char *temp, *s; + + do_v9 = xpg_echo; + display_return = 1; + + if (posixly_correct && xpg_echo) + goto just_echo; + + for (; list && (temp = list->word->word) && *temp == '-'; list = list->next) + { + /* If it appears that we are handling options, then make sure that + all of the options specified are actually valid. Otherwise, the + string should just be echoed. */ + temp++; + + for (i = 0; temp[i]; i++) + { + if (strchr (VALID_ECHO_OPTIONS, temp[i]) == 0) + break; + } + + /* echo - and echo -<nonopt> both mean to just echo the arguments. */ + if (*temp == 0 || temp[i]) + break; + + /* All of the options in TEMP are valid options to ECHO. + Handle them. */ + while (i = *temp++) + { + switch (i) + { + case 'n': + display_return = 0; + break; +#if defined (V9_ECHO) + case 'e': + do_v9 = 1; + break; + case 'E': + do_v9 = 0; + break; +#endif /* V9_ECHO */ + default: + goto just_echo; /* XXX */ + } + } + } + +just_echo: + + clearerr (stdout); /* clear error before writing and testing success */ + + while (list) + { + i = len = 0; + temp = do_v9 ? ansicstr (list->word->word, STRLEN (list->word->word), 1, &i, &len) + : list->word->word; + if (temp) + { + if (do_v9) + { + for (s = temp; len > 0; len--) + putchar (*s++); + } + else + printf ("%s", temp); +#if defined (SunOS5) + fflush (stdout); /* Fix for bug in SunOS 5.5 printf(3) */ +#endif + } + if (do_v9 && temp) + free (temp); + list = list->next; + if (i) + { + display_return = 0; + break; + } + if (list) + putchar(' '); + } + + if (display_return) + putchar ('\n'); + fflush (stdout); + if (ferror (stdout)) + { + sh_wrerror (); + clearerr (stdout); + return (EXECUTION_FAILURE); + } + return (EXECUTION_SUCCESS); +} |