1path_to_inst(4) File Formats path_to_inst(4)
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6 path_to_inst - device instance number file
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9 /etc/path_to_inst
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13 /etc/path_to_inst records mappings of physical device names to instance
14 numbers.
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17 The instance number of a device is encoded in its minor number, and is
18 the way that a device driver determines which of the possible devices
19 that it may drive is referred to by a given special file.
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22 In order to keep instance numbers persistent across reboots, the system
23 records them in /etc/path_to_inst.
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26 This file is read only at boot time, and is updated by add_drv(1M) and
27 devfsadm(1M).
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30 Note that it is generally not necessary for the system administrator to
31 change this file, as the system will maintain it.
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34 The system administrator can change the assignment of instance numbers
35 by editing this file and doing a reconfiguration reboot. However, any
36 changes made in this file will be lost if add_drv(1M) or devfsadm(1M)
37 is run before the system is rebooted.
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40 Each instance entry is a single line of the form:
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42 "physical name" instance number "driver binding name"
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46 where
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48 physical name is the absolute physical pathname of a device.
49 This pathname must be enclosed in double quotes.
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52 instance number is a decimal or hexadecimal number.
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55 driver binding name is the name used to determine the driver for the
56 device. This name may be a driver alias or a
57 driver name. The driver binding name must be
58 enclosed in double quotes.
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62 Example 1 Sample path_to_inst Entries
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65 Here are some sample path_to_inst entries:
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68 "/iommu@f,e0000000" 0 "iommu"
69 "/iommu@f,e0000000/sbus@f,e0001000" 0 "sbus"
70 "/iommu@f,e0000000/sbus@f,e0001000/sbusmem@e,0" 14 "sbusmem"
71 "/iommu@f,e0000000/sbus@f,e0001000/sbusmem@f,0" 15 "sbusmem"
72 "/iommu@f,e0000000/sbus@f,e0001000/ledma@f,400010" 0 "ledma"
73 "/obio/serial@0,100000" 0 "zs"
74 "/SUNW,sx@f,80000000" 0 "SUNW,sx"
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79 /etc/path_to_inst Mapping of physical device names to instance num‐
80 bers.
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84 add_drv(1M), boot(1M), devfsadm(1M), mknod(1M)
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87 If the file is removed the system may not be bootable (as it may rely
88 on information found in this file to find the root, usr or swap
89 device). If it does successfully boot, it will regenerate the file, but
90 after rebooting devices may end up having different minor numbers than
91 they did before, and special files created via mknod(1M) may refer to
92 different devices than expected.
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95 For the same reasons, changes should not be made to this file without
96 careful consideration.
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99 This document does not constitute an API. path_to_inst may not exist or
100 may have a different content or interpretation in a future release. The
101 existence of this notice does not imply that any other documentation
102 that lacks this notice constitutes an API.
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106SunOS 5.11 18 May 2007 path_to_inst(4)