GNU Rush
	Restricted User Shell	Sergey Poznyakoff

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7 Test Mode

GNU Rush provides a special test mode, intended to test configuration files and to emulate execution of commands. Test mode is enabled by the --test command line option (aliases: --lint, -t). When rush is given this option, the following occurs:

1. All diagnostic messages are redirected to standard error, instead of syslog.
2. If a single non-option argument is present, it is taken as a name of the configuration file to use.
3. The configuration file is parsed. If parsing fails, the program exits with the code 1.
4. If the -c option is present, rush processes its argument as usual (see Operation), except that the command itself is not executed.
5. Otherwise, if -i option is present, rush emulates interactive usage, but does not execute the final command.

An exit status of 0 means no errors, 1 means an error has occurred.

You can also emulate access by a particular user, by supplying his user name via the --user (-u) option. This option implies --test.

In test mode, you can set debugging level (see Debugging) from the command line, using the --debug (-d) command line option. It expects a single number specifying debugging level as its argument. The debugging level set this way overrides settings from the configuration file.

Here are several examples that illustrate the use of test mode in various cases:

1. Test default configuration file:

   $ rush --test
   

2. Test configuration file sample.rc:

   $ rush --test sample.rc
   

3. Test interactive access

   $ rush --test -i sample.rc
   

4. Test the configuration file and emulate execution of the command cvs server. Use debugging level 2:

   $ rush --test --debug=2 -c "cvs server"
   

5. Same, but for user ‘jeff’:

   $ rush --user=jeff --debug=2 -c "cvs server"
   

   Note, that you don’t need to specify --test along with --user or -i options.

6. Same, but use sample.rc instead of the default configuration file:

   $ rush --test --debug=2 -c "cvs server" sample.rc
   

7.1 Dump Mode

Dump mode is similar to test mode. The main difference is that in this mode, rush dumps to the standard output a description of the user request after performing all checks and transformations.

The mode is requested by the --dump=attr (-D attr) option. The argument attr is a comma-separated list of the names of attributes to be included in the dump, or the word ‘all’, standing for all attributes.

Additional options and arguments are the same as for the --test option.

The description is formatted as a JSON object⁵ with the following attributes. These are also the allowed values for the attr list:

cmdline

Command line after transformations.

argv

Array of command line arguments after transformations.

prog

Name of the program to be executed. If ‘null’, argv[0] will be used.

interactive

‘0’ for normal requests, ‘1’ for interactive requests.

pw_name

Name of the user from the system user database.

pw_uid

UID of the user.

pw_gid

GID of the user.

pw_dir

Home directory of the user, as set in the system user database.

umask

Value of the umask (octal).

chroot_dir

Chroot directory.

home_dir

Current working directory.

gid

New GID as set by the newgrp action, or ‘-1’ if unchanged.

fork

Fork mode. It is a three-state attribute: ‘0’ meaning disabled, ‘1’ meaning enabled, and ‘-1’ meaning default state.

acct

Accounting mode. See ‘fork’, for a description of possible values.

text_domain

Textual domain for i18n.

localedir

Locale directory for i18n.

locale

Locale name

environ

Dump of the environment (array of assignments).

vars

Defined variables, as a JSON object.

The attribute ‘all’ stands for all attribute in the same order as listed in the table above.