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

6       rsh, restricted_shell - restricted shell command interpreter
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SYNOPSIS

9       /usr/lib/rsh [-acefhiknprstuvx] [argument]...
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DESCRIPTION

13       rsh  is a limiting version of the standard command interpreter sh, used
14       to restrict logins to execution  environments  whose  capabilities  are
15       more  controlled  than  those of sh (see sh(1) for complete description
16       and usage).
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19       When the shell is invoked, it scans the environment for  the  value  of
20       the  environmental  variable, SHELL. If it is found and rsh is the file
21       name part of its value, the shell becomes a restricted shell.
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24       The actions of rsh are identical to those of sh, except that  the  fol‐
25       lowing are disallowed:
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27           o      changing directory (see cd(1)),
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29           o      setting the value of $PATH,
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31           o      pecifying path or command names containing /,
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33           o      redirecting output (> and >>).
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36       The restrictions above are enforced after .profile is interpreted.
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39       A restricted shell can be invoked in one of the following ways:
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41           1.     rsh  is  the  file  name  part  of  the  last  entry  in the
42                  /etc/passwd file (see passwd(4));
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44           2.     the environment variable SHELL exists and rsh  is  the  file
45                  name part of its value; the environment variable SHELL needs
46                  to be set in the .login file;
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48           3.     the shell is invoked and rsh is the file name part of  argu‐
49                  ment 0;
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51           4.     the shell is invoke with the -r option.
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54       When  a  command  to  be executed is found to be a shell procedure, rsh
55       invokes sh to execute it. Thus, it is possible to provide to  the  end-
56       user  shell procedures  that have access to the full power of the stan‐
57       dard shell, while imposing a limited  menu  of  commands;  this  scheme
58       assumes  that  the end-user does not have write and execute permissions
59       in the same directory.
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62       The net effect of these rules is that the writer of the  .profile  (see
63       profile(4))  has complete control over user actions by performing guar‐
64       anteed setup actions and leaving the user in an  appropriate  directory
65       (probably not the login directory).
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68       The  system  administrator  often sets up a directory of commands (that
69       is, /usr/rbin) that can be safely invoked by a restricted  shell.  Some
70       systems also provide a restricted editor, red.
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EXIT STATUS

73       Errors detected by the shell, such as syntax errors, cause the shell to
74       return a non-zero exit status. If the shell is being used  non-interac‐
75       tively  execution  of the shell file is abandoned. Otherwise, the shell
76       returns the exit status of the last command executed.
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ATTRIBUTES

79       See attributes(5) for descriptions of the following attributes:
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84       ┌─────────────────────────────┬─────────────────────────────┐
85       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
86       ├─────────────────────────────┼─────────────────────────────┤
87       │Availability                 │SUNWcsu                      │
88       └─────────────────────────────┴─────────────────────────────┘
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SEE ALSO

91       intro(1), cd(1), login(1), rsh(1),  sh(1),   exec(2),  passwd(4),  pro‐
92       file(4), attributes(5)
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NOTES

95       The  restricted  shell,  /usr/lib/rsh,  should not be confused with the
96       remote shell, /usr/bin/rsh, which is documented in rsh(1).
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100SunOS 5.11                        1 Nov 1993                           rsh(1M)
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