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rsh(1m) [opensolaris man page]

rsh(1M) 						  System Administration Commands						   rsh(1M)

NAME
rsh, restricted_shell - restricted shell command interpreter SYNOPSIS
/usr/lib/rsh [-acefhiknprstuvx] [argument]... DESCRIPTION
rsh is a limiting version of the standard command interpreter sh, used to restrict logins to execution environments whose capabilities are more controlled than those of sh (see sh(1) for complete description and usage). When the shell is invoked, it scans the environment for the value of the environmental variable, SHELL. If it is found and rsh is the file name part of its value, the shell becomes a restricted shell. The actions of rsh are identical to those of sh, except that the following are disallowed: o changing directory (see cd(1)), o setting the value of $PATH, o pecifying path or command names containing /, o redirecting output (> and >>). The restrictions above are enforced after .profile is interpreted. A restricted shell can be invoked in one of the following ways: 1. rsh is the file name part of the last entry in the /etc/passwd file (see passwd(4)); 2. the environment variable SHELL exists and rsh is the file name part of its value; the environment variable SHELL needs to be set in the .login file; 3. the shell is invoked and rsh is the file name part of argument 0; 4. the shell is invoke with the -r option. When a command to be executed is found to be a shell procedure, rsh invokes sh to execute it. Thus, it is possible to provide to the end- user shell procedures that have access to the full power of the standard shell, while imposing a limited menu of commands; this scheme assumes that the end-user does not have write and execute permissions in the same directory. The net effect of these rules is that the writer of the .profile (see profile(4)) has complete control over user actions by performing guaranteed setup actions and leaving the user in an appropriate directory (probably not the login directory). The system administrator often sets up a directory of commands (that is, /usr/rbin) that can be safely invoked by a restricted shell. Some systems also provide a restricted editor, red. EXIT STATUS
Errors detected by the shell, such as syntax errors, cause the shell to return a non-zero exit status. If the shell is being used non- interactively execution of the shell file is abandoned. Otherwise, the shell returns the exit status of the last command executed. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
intro(1), cd(1), login(1), rsh(1), sh(1), exec(2), passwd(4), profile(4), attributes(5) NOTES
The restricted shell, /usr/lib/rsh, should not be confused with the remote shell, /usr/bin/rsh, which is documented in rsh(1). SunOS 5.11 1 Nov 1993 rsh(1M)

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CHSH(1)                                                            User Commands                                                           CHSH(1)

NAME
chsh - change login shell SYNOPSIS
chsh [options] [LOGIN] DESCRIPTION
The chsh command changes the user login shell. This determines the name of the user's initial login command. A normal user may only change the login shell for her own account; the superuser may change the login shell for any account. OPTIONS
The options which apply to the chsh command are: -h, --help Display help message and exit. -R, --root CHROOT_DIR Apply changes in the CHROOT_DIR directory and use the configuration files from the CHROOT_DIR directory. -s, --shell SHELL The name of the user's new login shell. Setting this field to blank causes the system to select the default login shell. If the -s option is not selected, chsh operates in an interactive fashion, prompting the user with the current login shell. Enter the new value to change the shell, or leave the line blank to use the current one. The current shell is displayed between a pair of [ ] marks. NOTE
The only restriction placed on the login shell is that the command name must be listed in /etc/shells, unless the invoker is the superuser, and then any value may be added. An account with a restricted login shell may not change her login shell. For this reason, placing /bin/rsh in /etc/shells is discouraged since accidentally changing to a restricted shell would prevent the user from ever changing her login shell back to its original value. FILES
/etc/passwd User account information. /etc/shells List of valid login shells. /etc/login.defs Shadow password suite configuration. SEE ALSO
chfn(1), login.defs(5), passwd(5). shadow-utils 4.5 01/25/2018 CHSH(1)
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