1XDMSHELL(1) General Commands Manual XDMSHELL(1)
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6 xdmshell - shell for starting xdm on login
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9 /usr/bin/xdmshell
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12 Xdmshell can be used on systems that are configured to start a console
13 in text mode by default, to allow users to start the X display manager
14 by logging in as a special user with the shell set to the xdmshell pro‐
15 gram.
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17 Many servers set the keyboard to do non-blocking I/O under the assump‐
18 tion that they are the only programs attempting to read from the key‐
19 board. Unfortunately, some versions of getty(8) will immediately see a
20 continuous stream of zero-length reads which they interpret as end-of-
21 file indicators. Eventually, init(8) will disable logins on that line
22 until somebody types the following as root:
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24 On some platforms, one alternative is to disable logins on the console
25 and always run xdm(1) from /etc/inittab.
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27 Another approach is to set up an account whose shell is the xdmshell
28 program found in the xdm distribution. This program is not installed
29 by default so that site administrators will examine it to see if it
30 meets their needs. The xdmshell utility makes sure that it is being
31 run from the appropriate type of terminal, starts xdm, waits for it to
32 finish, and then resets the console if necessary. If the xdm resources
33 file (specified by the DisplayManager*resources entry in the xdm-config
34 file) contains a binding to the abort-display action similar to the
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36 xlogin*login.translations: #override Ctrl<Key>R: abort-dis‐
37 play()
38 the console can then by restored by pressing the indicated key (Con‐
39 trol-R in the above example) in the xdm login window.
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41 The xdmshell program is usually installed setuid to root but executable
42 only by members of a special group, of which the only member is the
43 account which has xdmshell as its shell:
44 % grep xdm /etc/passwd
45 x::101:51:Account for starting up X:/tmp:/usr/bin/xdmshell
46 % grep 51 /etc/group
47 xdmgrp:*:51:
48 % ls -lg /usr/bin/xdmshell
49 -rws--x--- 1 root xdmgrp 20338 Nov 1 01:32 /usr/bin/xdmshell
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51 If the xdm resources have not been configured to have a key bound to
52 the abort-display() action, there will be no way for general users to
53 login to the console directly. Whether or not this is desirable
54 depends on the particular site.
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57 X(7), xdm(1), xinit(1)
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61X Version 11 xdm 1.1.11 XDMSHELL(1)