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This file is echo.def, from which is created echo.c.
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It implements the builtin "echo" in Bash.
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Copyright (C) 1987-2009 Free Software Foundation, Inc.
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This file is part of GNU Bash, the Bourne Again SHell.
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Bash is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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Bash is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with Bash. If not, see <http://www.gnu.org/licenses/>.
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#if defined (HAVE_UNISTD_H)
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#include "../bashansi.h"
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$FUNCTION echo_builtin
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$SHORT_DOC echo [-neE] [arg ...]
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Write arguments to the standard output.
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Display the ARGs, separated by a single space character and followed by a
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newline, on the standard output.
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-n do not append a newline
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-e enable interpretation of the following backslash escapes
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-E explicitly suppress interpretation of backslash escapes
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`echo' interprets the following backslash-escaped characters:
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\c suppress further output
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\0nnn the character whose ASCII code is NNN (octal). NNN can be
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\xHH the eight-bit character whose value is HH (hexadecimal). HH
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can be one or two hex digits
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Returns success unless a write error occurs.
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$FUNCTION echo_builtin
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$SHORT_DOC echo [-n] [arg ...]
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Write arguments to the standard output.
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Display the ARGs on the standard output followed by a newline.
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-n do not append a newline
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Returns success unless a write error occurs.
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# define VALID_ECHO_OPTIONS "neE"
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# define VALID_ECHO_OPTIONS "n"
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/* System V machines already have a /bin/sh with a v9 behaviour. We
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give Bash the identical behaviour for these machines so that the
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existing system shells won't barf. Regrettably, the SUS v2 has
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standardized the Sys V echo behavior. This variable is external
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so that we can have a `shopt' variable to control it at runtime. */
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#if defined (DEFAULT_ECHO_TO_XPG) || defined (STRICT_POSIX)
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#endif /* DEFAULT_ECHO_TO_XPG */
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extern int posixly_correct;
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/* Print the words in LIST to standard output. If the first word is
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`-n', then don't print a trailing newline. We also support the
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echo syntax from Version 9 Unix systems. */
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int display_return, do_v9, i, len;
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if (posixly_correct && xpg_echo)
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for (; list && (temp = list->word->word) && *temp == '-'; list = list->next)
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/* If it appears that we are handling options, then make sure that
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all of the options specified are actually valid. Otherwise, the
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string should just be echoed. */
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for (i = 0; temp[i]; i++)
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if (strchr (VALID_ECHO_OPTIONS, temp[i]) == 0)
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/* echo - and echo -<nonopt> both mean to just echo the arguments. */
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if (*temp == 0 || temp[i])
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/* All of the options in TEMP are valid options to ECHO.
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#if defined (V9_ECHO)
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goto just_echo; /* XXX */
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clearerr (stdout); /* clear error before writing and testing success */
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terminate_immediately++;
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temp = do_v9 ? ansicstr (list->word->word, STRLEN (list->word->word), 1, &i, &len)
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for (s = temp; len > 0; len--)
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fflush (stdout); /* Fix for bug in SunOS 5.5 printf(3) */
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terminate_immediately--;
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return (sh_chkwrite (EXECUTION_SUCCESS));