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This file is set.def, from which is created set.c.
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It implements the "set" and "unset" builtins in Bash.
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Copyright (C) 1987-2012 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 <sys/types.h>
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#include "../bashansi.h"
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#include "../bashintl.h"
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#include "bashgetopt.h"
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#if defined (READLINE)
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# include "../input.h"
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# include "../bashline.h"
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# include <readline/readline.h>
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# include "../bashhist.h"
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extern int posixly_correct, ignoreeof, eof_encountered_limit;
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extern int dont_save_function_defs;
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#if defined (READLINE)
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extern int no_line_editing;
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$SHORT_DOC set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
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Set or unset values of shell options and positional parameters.
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Change the value of shell attributes and positional parameters, or
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display the names and values of shell variables.
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-a Mark variables which are modified or created for export.
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-b Notify of job termination immediately.
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-e Exit immediately if a command exits with a non-zero status.
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-f Disable file name generation (globbing).
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-h Remember the location of commands as they are looked up.
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-k All assignment arguments are placed in the environment for a
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command, not just those that precede the command name.
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-m Job control is enabled.
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-n Read commands but do not execute them.
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Set the variable corresponding to option-name:
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braceexpand same as -B
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#if defined (READLINE)
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emacs use an emacs-style line editing interface
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#if defined (BANG_HISTORY)
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#endif /* BANG_HISTORY */
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history enable command history
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ignoreeof the shell will not exit upon reading EOF
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allow comments to appear in interactive commands
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#if defined (JOB_CONTROL)
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nolog currently accepted but ignored
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#if defined (JOB_CONTROL)
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pipefail the return value of a pipeline is the status of
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the last command to exit with a non-zero status,
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or zero if no command exited with a non-zero status
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posix change the behavior of bash where the default
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operation differs from the Posix standard to
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privileged same as -p
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#if defined (READLINE)
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vi use a vi-style line editing interface
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#endif /* READLINE */
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-p Turned on whenever the real and effective user ids do not match.
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Disables processing of the $ENV file and importing of shell
126
functions. Turning this option off causes the effective uid and
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gid to be set to the real uid and gid.
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-t Exit after reading and executing one command.
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-u Treat unset variables as an error when substituting.
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-v Print shell input lines as they are read.
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-x Print commands and their arguments as they are executed.
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#if defined (BRACE_EXPANSION)
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-B the shell will perform brace expansion
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#endif /* BRACE_EXPANSION */
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-C If set, disallow existing regular files to be overwritten
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by redirection of output.
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-E If set, the ERR trap is inherited by shell functions.
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#if defined (BANG_HISTORY)
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-H Enable ! style history substitution. This flag is on
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by default when the shell is interactive.
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#endif /* BANG_HISTORY */
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-P If set, do not resolve symbolic links when executing commands
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such as cd which change the current directory.
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-T If set, the DEBUG trap is inherited by shell functions.
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-- Assign any remaining arguments to the positional parameters.
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If there are no remaining arguments, the positional parameters
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- Assign any remaining arguments to the positional parameters.
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The -x and -v options are turned off.
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Using + rather than - causes these flags to be turned off. The
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flags can also be used upon invocation of the shell. The current
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set of flags may be found in $-. The remaining n ARGs are positional
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parameters and are assigned, in order, to $1, $2, .. $n. If no
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ARGs are given, all shell variables are printed.
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Returns success unless an invalid option is given.
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typedef int setopt_set_func_t __P((int, char *));
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typedef int setopt_get_func_t __P((char *));
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static void print_minus_o_option __P((char *, int, int));
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static void print_all_shell_variables __P((void));
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static int set_ignoreeof __P((int, char *));
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static int set_posix_mode __P((int, char *));
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#if defined (READLINE)
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static int set_edit_mode __P((int, char *));
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static int get_edit_mode __P((char *));
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#if defined (HISTORY)
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static int bash_set_history __P((int, char *));
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static const char * const on = "on";
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static const char * const off = "off";
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/* A struct used to match long options for set -o to the corresponding
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option letter or internal variable. The functions can be called to
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dynamically generate values. */
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setopt_set_func_t *set_func;
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setopt_get_func_t *get_func;
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{ "allexport", 'a', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#if defined (BRACE_EXPANSION)
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{ "braceexpand",'B', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#if defined (READLINE)
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{ "emacs", '\0', (int *)NULL, set_edit_mode, get_edit_mode },
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{ "errexit", 'e', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "errtrace", 'E', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "functrace", 'T', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "hashall", 'h', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#if defined (BANG_HISTORY)
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{ "histexpand", 'H', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#endif /* BANG_HISTORY */
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#if defined (HISTORY)
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{ "history", '\0', &enable_history_list, bash_set_history, (setopt_get_func_t *)NULL },
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{ "ignoreeof", '\0', &ignoreeof, set_ignoreeof, (setopt_get_func_t *)NULL },
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{ "interactive-comments", '\0', &interactive_comments, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "keyword", 'k', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#if defined (JOB_CONTROL)
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{ "monitor", 'm', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "noclobber", 'C', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "noexec", 'n', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "noglob", 'f', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#if defined (HISTORY)
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{ "nolog", '\0', &dont_save_function_defs, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#if defined (JOB_CONTROL)
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{ "notify", 'b', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#endif /* JOB_CONTROL */
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{ "nounset", 'u', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "onecmd", 't', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "physical", 'P', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "pipefail", '\0', &pipefail_opt, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "posix", '\0', &posixly_correct, set_posix_mode, (setopt_get_func_t *)NULL },
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{ "privileged", 'p', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{ "verbose", 'v', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#if defined (READLINE)
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{ "vi", '\0', (int *)NULL, set_edit_mode, get_edit_mode },
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{ "xtrace", 'x', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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{(char *)NULL, 0 , (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
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#define N_O_OPTIONS (sizeof (o_options) / sizeof (o_options[0]))
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#define GET_BINARY_O_OPTION_VALUE(i, name) \
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((o_options[i].get_func) ? (*o_options[i].get_func) (name) \
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: (*o_options[i].variable))
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#define SET_BINARY_O_OPTION_VALUE(i, onoff, name) \
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((o_options[i].set_func) ? (*o_options[i].set_func) (onoff, name) \
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: (*o_options[i].variable = (onoff == FLAG_ON)))
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minus_o_option_value (name)
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for (i = 0; o_options[i].name; i++)
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if (STREQ (name, o_options[i].name))
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if (o_options[i].letter)
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on_or_off = find_flag (o_options[i].letter);
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return ((on_or_off == FLAG_UNKNOWN) ? -1 : *on_or_off);
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return (GET_BINARY_O_OPTION_VALUE (i, name));
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#define MINUS_O_FORMAT "%-15s\t%s\n"
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print_minus_o_option (name, value, pflag)
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printf (MINUS_O_FORMAT, name, value ? on : off);
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printf ("set %co %s\n", value ? '-' : '+', name);
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list_minus_o_opts (mode, reusable)
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int *on_or_off, value;
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for (i = 0; o_options[i].name; i++)
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if (o_options[i].letter)
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on_or_off = find_flag (o_options[i].letter);
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if (on_or_off == FLAG_UNKNOWN)
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if (mode == -1 || mode == *on_or_off)
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print_minus_o_option (o_options[i].name, *on_or_off, reusable);
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value = GET_BINARY_O_OPTION_VALUE (i, o_options[i].name);
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if (mode == -1 || mode == value)
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print_minus_o_option (o_options[i].name, value, reusable);
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ret = strvec_create (N_O_OPTIONS + 1);
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for (i = 0; o_options[i].name; i++)
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ret[i] = o_options[i].name;
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ret[i] = (char *)NULL;
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set_ignoreeof (on_or_off, option_name)
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ignoreeof = on_or_off == FLAG_ON;
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unbind_variable ("ignoreeof");
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bind_variable ("IGNOREEOF", "10", 0);
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unbind_variable ("IGNOREEOF");
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sv_ignoreeof ("IGNOREEOF");
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set_posix_mode (on_or_off, option_name)
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posixly_correct = on_or_off == FLAG_ON;
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if (posixly_correct == 0)
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unbind_variable ("POSIXLY_CORRECT");
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bind_variable ("POSIXLY_CORRECT", "y", 0);
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sv_strict_posix ("POSIXLY_CORRECT");
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#if defined (READLINE)
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/* Magic. This code `knows' how readline handles rl_editing_mode. */
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set_edit_mode (on_or_off, option_name)
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if (on_or_off == FLAG_ON)
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rl_variable_bind ("editing-mode", option_name);
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with_input_from_stdin ();
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isemacs = rl_editing_mode == 1;
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if ((isemacs && *option_name == 'e') || (!isemacs && *option_name == 'v'))
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with_input_from_stream (stdin, "stdin");
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return 1-no_line_editing;
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return (*name == 'e' ? no_line_editing == 0 && rl_editing_mode == 1
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: no_line_editing == 0 && rl_editing_mode == 0);
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#endif /* READLINE */
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#if defined (HISTORY)
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bash_set_history (on_or_off, option_name)
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if (on_or_off == FLAG_ON)
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enable_history_list = 1;
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bash_history_enable ();
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if (history_lines_this_session == 0)
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enable_history_list = 0;
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bash_history_disable ();
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return (1 - enable_history_list);
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set_minus_o_option (on_or_off, option_name)
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for (i = 0; o_options[i].name; i++)
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if (STREQ (option_name, o_options[i].name))
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if (o_options[i].letter == 0)
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SET_BINARY_O_OPTION_VALUE (i, on_or_off, option_name);
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return (EXECUTION_SUCCESS);
433
if (change_flag (o_options[i].letter, on_or_off) == FLAG_ERROR)
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sh_invalidoptname (option_name);
436
return (EXECUTION_FAILURE);
439
return (EXECUTION_SUCCESS);
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sh_invalidoptname (option_name);
450
print_all_shell_variables ()
454
vars = all_shell_variables ();
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print_var_list (vars);
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/* POSIX.2 does not allow function names and definitions to be output when
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`set' is invoked without options (PASC Interp #202). */
463
if (posixly_correct == 0)
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vars = all_shell_functions ();
468
print_func_list (vars);
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char tflag[N_O_OPTIONS];
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int vsize, i, vptr, *ip, exported;
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for (vsize = i = 0; o_options[i].name; i++)
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if (o_options[i].letter)
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ip = find_flag (o_options[i].letter);
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vsize += strlen (o_options[i].name) + 1;
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else if (GET_BINARY_O_OPTION_VALUE (i, o_options[i].name))
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vsize += strlen (o_options[i].name) + 1;
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value = (char *)xmalloc (vsize + 1);
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for (i = vptr = 0; o_options[i].name; i++)
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strcpy (value + vptr, o_options[i].name);
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vptr += strlen (o_options[i].name);
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vptr--; /* cut off trailing colon */
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v = find_variable ("SHELLOPTS");
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/* Turn off the read-only attribute so we can bind the new value, and
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note whether or not the variable was exported. */
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VUNSETATTR (v, att_readonly);
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exported = exported_p (v);
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v = bind_variable ("SHELLOPTS", value, 0);
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/* Turn the read-only attribute back on, and turn off the export attribute
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if it was set implicitly by mark_modified_vars and SHELLOPTS was not
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exported before we bound the new value. */
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VSETATTR (v, att_readonly);
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if (mark_modified_vars && exported == 0 && exported_p (v))
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VUNSETATTR (v, att_exported);
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parse_shellopts (value)
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while (vname = extract_colon_unit (value, &vptr))
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set_minus_o_option (FLAG_ON, vname);
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initialize_shell_options (no_shellopts)
563
if (no_shellopts == 0)
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var = find_variable ("SHELLOPTS");
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/* set up any shell options we may have inherited. */
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if (var && imported_p (var))
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temp = (array_p (var) || assoc_p (var)) ? (char *)NULL : savestring (value_cell (var));
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parse_shellopts (temp);
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/* Set up the $SHELLOPTS variable. */
582
/* Reset the values of the -o options that are not also shell flags. This is
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called from execute_cmd.c:initialize_subshell() when setting up a subshell
584
to run an executable shell script without a leading `#!'. */
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reset_shell_options ()
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#if defined (HISTORY)
589
remember_on_history = enable_history_list = 1;
594
/* Set some flags from the word values in the input list. If LIST is empty,
595
then print out the values of the variables instead. If LIST contains
596
non-flags, then set $1 - $9 to the successive words of LIST. */
601
int on_or_off, flag_name, force_assignment, opts_changed, rv, r;
607
print_all_shell_variables ();
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return (sh_chkwrite (EXECUTION_SUCCESS));
611
/* Check validity of flag arguments. */
612
rv = EXECUTION_SUCCESS;
613
reset_internal_getopt ();
614
while ((flag_name = internal_getopt (list, optflags)) != -1)
620
return (list_optopt == '?' ? EXECUTION_SUCCESS : EX_USAGE);
626
/* Do the set command. While the list consists of words starting with
627
'-' or '+' treat them as flags, otherwise, start assigning them to
629
for (force_assignment = opts_changed = 0; list; )
631
arg = list->word->word;
633
/* If the argument is `--' or `-' then signal the end of the list
634
and remember the remaining arguments. */
635
if (arg[0] == '-' && (!arg[1] || (arg[1] == '-' && !arg[2])))
639
/* `set --' unsets the positional parameters. */
641
force_assignment = 1;
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/* Until told differently, the old shell behaviour of
644
`set - [arg ...]' being equivalent to `set +xv [arg ...]'
645
stands. Posix.2 says the behaviour is marked as obsolescent. */
648
change_flag ('x', '+');
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change_flag ('v', '+');
656
if ((on_or_off = *arg) && (on_or_off == '-' || on_or_off == '+'))
658
while (flag_name = *++arg)
660
if (flag_name == '?')
663
return (EXECUTION_SUCCESS);
665
else if (flag_name == 'o') /* -+o option-name */
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list_minus_o_opts (-1, (on_or_off == '+'));
675
rv = sh_chkwrite (rv);
679
option_name = opt->word->word;
681
if (option_name == 0 || *option_name == '\0' ||
682
*option_name == '-' || *option_name == '+')
684
list_minus_o_opts (-1, (on_or_off == '+'));
687
list = list->next; /* Skip over option name. */
690
if ((r = set_minus_o_option (on_or_off, option_name)) != EXECUTION_SUCCESS)
696
else if (change_flag (flag_name, on_or_off) == FLAG_ERROR)
704
return (EXECUTION_FAILURE);
716
/* Assigning $1 ... $n */
717
if (list || force_assignment)
718
remember_args (list, 1);
719
/* Set up new value of $SHELLOPTS */
726
$FUNCTION unset_builtin
727
$SHORT_DOC unset [-f] [-v] [-n] [name ...]
728
Unset values and attributes of shell variables and functions.
730
For each NAME, remove the corresponding variable or function.
733
-f treat each NAME as a shell function
734
-v treat each NAME as a shell variable
735
-n treat each NAME as a name reference and unset the variable itself
736
rather than the variable it references
738
Without options, unset first tries to unset a variable, and if that fails,
739
tries to unset a function.
741
Some variables cannot be unset; also see `readonly'.
744
Returns success unless an invalid option is given or a NAME is read-only.
747
#define NEXT_VARIABLE() any_failed++; list = list->next; continue;
753
int unset_function, unset_variable, unset_array, opt, nameref, any_failed;
756
unset_function = unset_variable = unset_array = nameref = any_failed = 0;
758
reset_internal_getopt ();
759
while ((opt = internal_getopt (list, "fnv")) != -1)
780
if (unset_function && unset_variable)
782
builtin_error (_("cannot simultaneously unset a function and a variable"));
783
return (EXECUTION_FAILURE);
785
else if (unset_function && nameref)
792
#if defined (ARRAY_VARS)
796
name = list->word->word;
798
#if defined (ARRAY_VARS)
800
if (!unset_function && valid_array_reference (name))
802
t = strchr (name, '[');
807
/* Get error checking out of the way first. The low-level functions
808
just perform the unset, relying on the caller to verify. */
810
/* Bash allows functions with names which are not valid identifiers
811
to be created when not in posix mode, so check only when in posix
812
mode when unsetting a function. */
813
if (((unset_function && posixly_correct) || !unset_function) && legal_identifier (name) == 0)
819
/* Only search for functions here if -f supplied. */
820
var = unset_function ? find_function (name)
821
: (nameref ? find_variable_last_nameref (name) : find_variable (name));
823
/* Some variables (but not functions yet) cannot be unset, period. */
824
if (var && unset_function == 0 && non_unsettable_p (var))
826
builtin_error (_("%s: cannot unset"), name);
830
/* Posix.2 says try variables first, then functions. If we would
831
find a function after unsuccessfully searching for a variable,
832
note that we're acting on a function now as if -f were
833
supplied. The readonly check below takes care of it. */
834
if (var == 0 && unset_variable == 0 && unset_function == 0)
836
if (var = find_function (name))
840
/* Posix.2 says that unsetting readonly variables is an error. */
841
if (var && readonly_p (var))
843
builtin_error (_("%s: cannot unset: readonly %s"),
844
var->name, unset_function ? "function" : "variable");
848
/* Unless the -f option is supplied, the name refers to a variable. */
849
#if defined (ARRAY_VARS)
850
if (var && unset_array)
852
if (array_p (var) == 0 && assoc_p (var) == 0)
854
builtin_error (_("%s: not an array variable"), var->name);
859
tem = unbind_array_element (var, t);
865
#endif /* ARRAY_VARS */
866
tem = unset_function ? unbind_func (name) : (nameref ? unbind_nameref (name) : unbind_variable (name));
868
/* This is what Posix.2 says: ``If neither -f nor -v
869
is specified, the name refers to a variable; if a variable by
870
that name does not exist, a function by that name, if any,
872
if (tem == -1 && unset_function == 0 && unset_variable == 0)
873
tem = unbind_func (name);
875
/* SUSv3, POSIX.1-2001 say: ``Unsetting a variable or function that
876
was not previously set shall not be considered an error.'' */
878
if (unset_function == 0)
879
stupidly_hack_special_variables (name);
884
return (any_failed ? EXECUTION_FAILURE : EXECUTION_SUCCESS);
added
removed
builtins/set.def
