[821] | 1 | #
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| 2 | # For a description of the syntax of this configuration file,
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| 3 | # see scripts/kbuild/config-language.txt.
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| 4 | #
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| 5 |
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| 6 | menu "Linux System Utilities"
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| 7 |
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[1765] | 8 | config DMESG
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[821] | 9 | bool "dmesg"
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| 10 | default n
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| 11 | help
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| 12 | dmesg is used to examine or control the kernel ring buffer. When the
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| 13 | Linux kernel prints messages to the system log, they are stored in
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| 14 | the kernel ring buffer. You can use dmesg to print the kernel's ring
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| 15 | buffer, clear the kernel ring buffer, change the size of the kernel
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| 16 | ring buffer, and change the priority level at which kernel messages
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| 17 | are also logged to the system console. Enable this option if you
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| 18 | wish to enable the 'dmesg' utility.
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| 19 |
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[1765] | 20 | config FEATURE_DMESG_PRETTY
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| 21 | bool "pretty dmesg output"
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| 22 | default y
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| 23 | depends on DMESG
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| 24 | help
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| 25 | If you wish to scrub the syslog level from the output, say 'Y' here.
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| 26 | The syslog level is a string prefixed to every line with the form "<#>".
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| 27 |
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| 28 | With this option you will see:
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| 29 | # dmesg
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| 30 | Linux version 2.6.17.4 .....
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| 31 | BIOS-provided physical RAM map:
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| 32 | BIOS-e820: 0000000000000000 - 000000000009f000 (usable)
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| 33 |
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| 34 | Without this option you will see:
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| 35 | # dmesg
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| 36 | <5>Linux version 2.6.17.4 .....
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| 37 | <6>BIOS-provided physical RAM map:
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| 38 | <6> BIOS-e820: 0000000000000000 - 000000000009f000 (usable)
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| 39 |
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| 40 | config FBSET
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[821] | 41 | bool "fbset"
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| 42 | default n
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| 43 | help
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| 44 | fbset is used to show or change the settings of a Linux frame buffer
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| 45 | device. The frame buffer device provides a simple and unique
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| 46 | interface to access a graphics display. Enable this option
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| 47 | if you wish to enable the 'fbset' utility.
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| 48 |
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[1765] | 49 | config FEATURE_FBSET_FANCY
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[821] | 50 | bool "Turn on extra fbset options"
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| 51 | default n
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[1765] | 52 | depends on FBSET
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[821] | 53 | help
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| 54 | This option enables extended fbset options, allowing one to set the
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| 55 | framebuffer size, color depth, etc. interface to access a graphics
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| 56 | display. Enable this option if you wish to enable extended fbset
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| 57 | options.
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| 58 |
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[1765] | 59 | config FEATURE_FBSET_READMODE
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[821] | 60 | bool "Turn on fbset readmode support"
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| 61 | default n
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[1765] | 62 | depends on FBSET
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[821] | 63 | help
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| 64 | This option allows fbset to read the video mode database stored by
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| 65 | default as /etc/fb.modes, which can be used to set frame buffer
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| 66 | device to pre-defined video modes.
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| 67 |
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[1765] | 68 | config FDFLUSH
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[821] | 69 | bool "fdflush"
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| 70 | default n
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| 71 | help
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| 72 | fdflush is only needed when changing media on slightly-broken
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| 73 | removable media drives. It is used to make Linux believe that a
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| 74 | hardware disk-change switch has been actuated, which causes Linux to
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| 75 | forget anything it has cached from the previous media. If you have
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| 76 | such a slightly-broken drive, you will need to run fdflush every time
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| 77 | you change a disk. Most people have working hardware and can safely
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| 78 | leave this disabled.
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| 79 |
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[1765] | 80 | config FDFORMAT
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[821] | 81 | bool "fdformat"
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| 82 | default n
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| 83 | help
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| 84 | fdformat is used to low-level format a floppy disk.
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| 85 |
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[1765] | 86 | config FDISK
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[821] | 87 | bool "fdisk"
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| 88 | default n
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| 89 | help
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| 90 | The fdisk utility is used to divide hard disks into one or more
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| 91 | logical disks, which are generally called partitions. This utility
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| 92 | can be used to list and edit the set of partitions or BSD style
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| 93 | 'disk slices' that are defined on a hard drive.
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| 94 |
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| 95 | config FDISK_SUPPORT_LARGE_DISKS
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| 96 | bool "support over 4GB disks"
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| 97 | default y
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[1765] | 98 | depends on FDISK
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[821] | 99 | help
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| 100 | Enable this option to support large disks > 4GB.
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| 101 |
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[1765] | 102 | config FEATURE_FDISK_WRITABLE
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[821] | 103 | bool "Write support"
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| 104 | default y
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[1765] | 105 | depends on FDISK
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[821] | 106 | help
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| 107 | Enabling this option allows you to create or change a partition table
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| 108 | and write those changes out to disk. If you leave this option
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| 109 | disabled, you will only be able to view the partition table.
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| 110 |
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[1765] | 111 | config FEATURE_AIX_LABEL
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[821] | 112 | bool "Support AIX disklabels"
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| 113 | default n
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[1765] | 114 | depends on FDISK && FEATURE_FDISK_WRITABLE
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[821] | 115 | help
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| 116 | Enabling this option allows you to create or change AIX disklabels.
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| 117 | Most people can safely leave this option disabled.
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| 118 |
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[1765] | 119 | config FEATURE_SGI_LABEL
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[821] | 120 | bool "Support SGI disklabels"
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| 121 | default n
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[1765] | 122 | depends on FDISK && FEATURE_FDISK_WRITABLE
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[821] | 123 | help
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| 124 | Enabling this option allows you to create or change SGI disklabels.
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| 125 | Most people can safely leave this option disabled.
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| 126 |
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[1765] | 127 | config FEATURE_SUN_LABEL
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[821] | 128 | bool "Support SUN disklabels"
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| 129 | default n
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[1765] | 130 | depends on FDISK && FEATURE_FDISK_WRITABLE
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[821] | 131 | help
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| 132 | Enabling this option allows you to create or change SUN disklabels.
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| 133 | Most people can safely leave this option disabled.
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| 134 |
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[1765] | 135 | config FEATURE_OSF_LABEL
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[821] | 136 | bool "Support BSD disklabels"
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| 137 | default n
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[1765] | 138 | depends on FDISK && FEATURE_FDISK_WRITABLE
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[821] | 139 | help
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| 140 | Enabling this option allows you to create or change BSD disklabels
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| 141 | and define and edit BSD disk slices.
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| 142 |
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[1765] | 143 | config FEATURE_FDISK_ADVANCED
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[821] | 144 | bool "Support expert mode"
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| 145 | default n
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[1765] | 146 | depends on FDISK && FEATURE_FDISK_WRITABLE
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[821] | 147 | help
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| 148 | Enabling this option allows you to do terribly unsafe things like
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| 149 | define arbitrary drive geometry, move the beginning of data in a
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| 150 | partition, and similarly evil things. Unless you have a very good
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| 151 | reason you would be wise to leave this disabled.
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| 152 |
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[1765] | 153 | config FREERAMDISK
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[821] | 154 | bool "freeramdisk"
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| 155 | default n
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| 156 | help
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| 157 | Linux allows you to create ramdisks. This utility allows you to
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| 158 | delete them and completely free all memory that was used for the
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| 159 | ramdisk. For example, if you boot Linux into a ramdisk and later
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| 160 | pivot_root, you may want to free the memory that is allocated to the
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| 161 | ramdisk. If you have no use for freeing memory from a ramdisk, leave
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| 162 | this disabled.
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| 163 |
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[1765] | 164 | config FSCK_MINIX
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[821] | 165 | bool "fsck_minix"
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| 166 | default n
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| 167 | help
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| 168 | The minix filesystem is a nice, small, compact, read-write filesystem
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| 169 | with little overhead. It is not a journaling filesystem however and
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| 170 | can experience corruption if it is not properly unmounted or if the
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| 171 | power goes off in the middle of a write. This utility allows you to
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| 172 | check for and attempt to repair any corruption that occurs to a minix
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| 173 | filesystem.
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| 174 |
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[1765] | 175 | config MKFS_MINIX
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[821] | 176 | bool "mkfs_minix"
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| 177 | default n
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| 178 | help
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| 179 | The minix filesystem is a nice, small, compact, read-write filesystem
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| 180 | with little overhead. If you wish to be able to create minix filesystems
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| 181 | this utility will do the job for you.
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| 182 |
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| 183 | comment "Minix filesystem support"
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[1765] | 184 | depends on FSCK_MINIX || MKFS_MINIX
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[821] | 185 |
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[1765] | 186 | config FEATURE_MINIX2
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[821] | 187 | bool "Support Minix fs v2 (fsck_minix/mkfs_minix)"
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| 188 | default y
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[1765] | 189 | depends on FSCK_MINIX || MKFS_MINIX
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[821] | 190 | help
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| 191 | If you wish to be able to create version 2 minix filesystems, enable this.
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| 192 | If you enabled 'mkfs_minix' then you almost certainly want to be using the
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| 193 | version 2 filesystem support.
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| 194 |
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[1765] | 195 | config GETOPT
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[821] | 196 | bool "getopt"
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| 197 | default n
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| 198 | help
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| 199 | The getopt utility is used to break up (parse) options in command
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| 200 | lines to make it easy to write complex shell scripts that also check
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| 201 | for legal (and illegal) options. If you want to write horribly
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| 202 | complex shell scripts, or use some horribly complex shell script
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| 203 | written by others, this utility may be for you. Most people will
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| 204 | wisely leave this disabled.
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| 205 |
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[1765] | 206 | config HEXDUMP
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[821] | 207 | bool "hexdump"
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| 208 | default n
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| 209 | help
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| 210 | The hexdump utility is used to display binary data in a readable
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| 211 | way that is comparable to the output from most hex editors.
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| 212 |
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[1765] | 213 | config HWCLOCK
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[821] | 214 | bool "hwclock"
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| 215 | default n
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| 216 | help
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| 217 | The hwclock utility is used to read and set the hardware clock
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| 218 | on a system. This is primarily used to set the current time on
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| 219 | shutdown in the hardware clock, so the hardware will keep the
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| 220 | correct time when Linux is _not_ running.
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| 221 |
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[1765] | 222 | config FEATURE_HWCLOCK_LONG_OPTIONS
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[821] | 223 | bool "Support long options (--hctosys,...)"
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| 224 | default n
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[1765] | 225 | depends on HWCLOCK && GETOPT_LONG
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[821] | 226 | help
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| 227 | By default, the hwclock utility only uses short options. If you
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| 228 | are overly fond of its long options, such as --hctosys, --utc, etc)
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| 229 | then enable this option.
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| 230 |
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[1765] | 231 | config FEATURE_HWCLOCK_ADJTIME_FHS
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[821] | 232 | bool "Use FHS /var/lib/hwclock/adjtime"
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| 233 | default y
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[1765] | 234 | depends on HWCLOCK
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[821] | 235 | help
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| 236 | Starting with FHS 2.3, the adjtime state file is supposed to exist
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| 237 | at /var/lib/hwclock/adjtime instead of /etc/adjtime. If you wish
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| 238 | to use the FHS behavior, answer Y here, otherwise answer N for the
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| 239 | classic /etc/adjtime path.
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| 240 |
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| 241 | http://www.pathname.com/fhs/pub/fhs-2.3.html#VARLIBHWCLOCKSTATEDIRECTORYFORHWCLO
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| 242 |
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[1765] | 243 | config IPCRM
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[821] | 244 | bool "ipcrm"
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| 245 | default n
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[1765] | 246 | select FEATURE_SUID
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[821] | 247 | help
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| 248 | The ipcrm utility allows the removal of System V interprocess
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| 249 | communication (IPC) objects and the associated data structures
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| 250 | from the system.
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| 251 |
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[1765] | 252 | config IPCS
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[821] | 253 | bool "ipcs"
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| 254 | default n
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[1765] | 255 | select FEATURE_SUID
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[821] | 256 | help
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| 257 | The ipcs utility is used to provide information on the currently
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| 258 | allocated System V interprocess (IPC) objects in the system.
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| 259 |
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[1765] | 260 | config LOSETUP
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[821] | 261 | bool "losetup"
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| 262 | default n
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| 263 | help
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| 264 | losetup is used to associate or detach a loop device with a regular
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| 265 | file or block device, and to query the status of a loop device. This
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| 266 | version does not currently support enabling data encryption.
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| 267 |
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[1765] | 268 | config MDEV
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[821] | 269 | bool "mdev"
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| 270 | default n
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| 271 | help
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[1765] | 272 | mdev is a mini-udev implementation for dynamically creating device
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| 273 | nodes in the /dev directory.
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[821] | 274 |
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[1765] | 275 | For more information, please see docs/mdev.txt
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| 276 |
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| 277 | config FEATURE_MDEV_CONF
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[821] | 278 | bool "Support /etc/mdev.conf"
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| 279 | default n
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[1765] | 280 | depends on MDEV
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[821] | 281 | help
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[1765] | 282 | Add support for the mdev config file to control ownership and
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| 283 | permissions of the device nodes.
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[821] | 284 |
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[1765] | 285 | For more information, please see docs/mdev.txt
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[821] | 286 |
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[1765] | 287 | config FEATURE_MDEV_EXEC
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[821] | 288 | bool "Support command execution at device addition/removal"
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| 289 | default n
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[1765] | 290 | depends on FEATURE_MDEV_CONF
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[821] | 291 | help
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[1765] | 292 | This adds support for an optional field to /etc/mdev.conf for
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| 293 | executing commands when devices are created/removed.
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[821] | 294 |
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[1765] | 295 | For more information, please see docs/mdev.txt
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[821] | 296 |
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[1765] | 297 | config FEATURE_MDEV_LOAD_FIRMWARE
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| 298 | bool "Support loading of firmwares"
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| 299 | default n
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| 300 | depends on MDEV
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| 301 | help
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| 302 | Some devices need to load firmware before they can be usable.
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[821] | 303 |
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[1765] | 304 | These devices will request userspace look up the files in
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| 305 | /lib/firmware/ and if it exists, send it to the kernel for
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| 306 | loading into the hardware.
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[821] | 307 |
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[1765] | 308 | config MKSWAP
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[821] | 309 | bool "mkswap"
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| 310 | default n
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| 311 | help
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| 312 | The mkswap utility is used to configure a file or disk partition as
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| 313 | Linux swap space. This allows Linux to use the entire file or
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| 314 | partition as if it were additional RAM, which can greatly increase
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| 315 | the capability of low-memory machines. This additional memory is
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| 316 | much slower than real RAM, but can be very helpful at preventing your
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| 317 | applications being killed by the Linux out of memory (OOM) killer.
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| 318 | Once you have created swap space using 'mkswap' you need to enable
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| 319 | the swap space using the 'swapon' utility.
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| 320 |
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[1765] | 321 | config FEATURE_MKSWAP_V0
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[821] | 322 | bool "version 0 support"
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| 323 | default n
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[1765] | 324 | depends on MKSWAP
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| 325 | # depends on MKSWAP && DEPRECATED
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[821] | 326 | help
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| 327 | Enable support for the old v0 style.
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| 328 | If your kernel is older than 2.1.117, then v0 support is the
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| 329 | only option.
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| 330 |
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[1765] | 331 | config MORE
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[821] | 332 | bool "more"
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| 333 | default n
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| 334 | help
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| 335 | more is a simple utility which allows you to read text one screen
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| 336 | sized page at a time. If you want to read text that is larger than
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| 337 | the screen, and you are using anything faster than a 300 baud modem,
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| 338 | you will probably find this utility very helpful. If you don't have
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| 339 | any need to reading text files, you can leave this disabled.
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| 340 |
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[1765] | 341 | config FEATURE_USE_TERMIOS
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[821] | 342 | bool "Use termios to manipulate the screen"
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| 343 | default y
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[1765] | 344 | depends on MORE
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[821] | 345 | help
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| 346 | This option allows utilities such as 'more' and 'top' to determine
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| 347 | the size of the screen. If you leave this disabled, your utilities
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| 348 | that display things on the screen will be especially primitive and
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| 349 | will be unable to determine the current screen size, and will be
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| 350 | unable to move the cursor.
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| 351 |
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[1765] | 352 | config MOUNT
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[821] | 353 | bool "mount"
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| 354 | default n
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| 355 | help
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| 356 | All files and filesystems in Unix are arranged into one big directory
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| 357 | tree. The 'mount' utility is used to graft a filesystem onto a
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| 358 | particular part of the tree. A filesystem can either live on a block
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| 359 | device, or it can be accessible over the network, as is the case with
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| 360 | NFS filesystems. Most people using BusyBox will also want to enable
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| 361 | the 'mount' utility.
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| 362 |
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[1765] | 363 | config FEATURE_MOUNT_NFS
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[821] | 364 | bool "Support mounting NFS file systems"
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| 365 | default n
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[1765] | 366 | depends on MOUNT
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| 367 | select FEATURE_HAVE_RPC
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| 368 | select FEATURE_SYSLOG
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[821] | 369 | help
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[1765] | 370 | Enable mounting of NFS file systems.
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[821] | 371 |
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[1765] | 372 | config FEATURE_MOUNT_CIFS
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| 373 | bool "Support mounting CIFS/SMB file systems"
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| 374 | default n
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| 375 | depends on MOUNT
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| 376 | help
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| 377 | Enable support for samba mounts.
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| 378 |
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| 379 | config FEATURE_MOUNT_FLAGS
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| 380 | depends on MOUNT
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| 381 | bool "Support lots of -o flags in mount"
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| 382 | default y
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| 383 | help
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| 384 | Without this, mount only supports ro/rw/remount. With this, it
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| 385 | supports nosuid, suid, dev, nodev, exec, noexec, sync, async, atime,
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| 386 | noatime, diratime, nodiratime, loud, bind, move, shared, slave,
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| 387 | private, unbindable, rshared, rslave, rprivate, and runbindable.
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| 388 |
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| 389 | config FEATURE_MOUNT_FSTAB
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| 390 | depends on MOUNT
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| 391 | bool "Support /etc/fstab and -a"
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| 392 | default y
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| 393 | help
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| 394 | Support mount all and looking for files in /etc/fstab.
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| 395 |
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| 396 | config PIVOT_ROOT
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[821] | 397 | bool "pivot_root"
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| 398 | default n
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| 399 | help
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| 400 | The pivot_root utility swaps the mount points for the root filesystem
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| 401 | with some other mounted filesystem. This allows you to do all sorts
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| 402 | of wild and crazy things with your Linux system and is far more
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| 403 | powerful than 'chroot'.
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| 404 |
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| 405 | Note: This is for initrd in linux 2.4. Under initramfs (introduced
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| 406 | in linux 2.6) use switch_root instead.
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| 407 |
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[1765] | 408 | config RDATE
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[821] | 409 | bool "rdate"
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| 410 | default n
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| 411 | help
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| 412 | The rdate utility allows you to synchronize the date and time of your
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| 413 | system clock with the date and time of a remote networked system using
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| 414 | the RFC868 protocol, which is built into the inetd daemon on most
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| 415 | systems.
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| 416 |
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[1765] | 417 | config READPROFILE
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[821] | 418 | bool "readprofile"
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| 419 | default n
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| 420 | help
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| 421 | This allows you to parse /proc/profile for basic profiling.
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| 422 |
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[1765] | 423 | config SETARCH
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[821] | 424 | bool "setarch"
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| 425 | default n
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| 426 | help
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| 427 | The linux32 utility is used to create a 32bit environment for the
|
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| 428 | specified program (usually a shell). It only makes sense to have
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| 429 | this util on a system that supports both 64bit and 32bit userland
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| 430 | (like amd64/x86, ppc64/ppc, sparc64/sparc, etc...).
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| 431 |
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[1765] | 432 | config SWAPONOFF
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[821] | 433 | bool "swaponoff"
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| 434 | default n
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| 435 | help
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| 436 | This option enables both the 'swapon' and the 'swapoff' utilities.
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| 437 | Once you have created some swap space using 'mkswap', you also need
|
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| 438 | to enable your swap space with the 'swapon' utility. The 'swapoff'
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| 439 | utility is used, typically at system shutdown, to disable any swap
|
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| 440 | space. If you are not using any swap space, you can leave this
|
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| 441 | option disabled.
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| 442 |
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[1765] | 443 | config SWITCH_ROOT
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[821] | 444 | bool "switch_root"
|
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| 445 | default n
|
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| 446 | help
|
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| 447 | The switch_root utility is used from initramfs to select a new
|
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| 448 | root device. Under initramfs, you have to use this instead of
|
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| 449 | pivot_root. (Stop reading here if you don't care why.)
|
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| 450 |
|
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| 451 | Booting with initramfs extracts a gzipped cpio archive into rootfs
|
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| 452 | (which is a variant of ramfs/tmpfs). Because rootfs can't be moved
|
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| 453 | or unmounted*, pivot_root will not work from initramfs. Instead,
|
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| 454 | switch_root deletes everything out of rootfs (including itself),
|
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| 455 | does a mount --move that overmounts rootfs with the new root, and
|
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| 456 | then execs the specified init program.
|
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| 457 |
|
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| 458 | * Because the Linux kernel uses rootfs internally as the starting
|
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| 459 | and ending point for searching through the kernel's doubly linked
|
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| 460 | list of active mount points. That's why.
|
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| 461 |
|
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[1765] | 462 | config UMOUNT
|
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[821] | 463 | bool "umount"
|
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| 464 | default n
|
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| 465 | help
|
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| 466 | When you want to remove a mounted filesystem from its current mount point,
|
---|
| 467 | for example when you are shutting down the system, the 'umount' utility is
|
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| 468 | the tool to use. If you enabled the 'mount' utility, you almost certainly
|
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| 469 | also want to enable 'umount'.
|
---|
| 470 |
|
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[1765] | 471 | config FEATURE_UMOUNT_ALL
|
---|
[821] | 472 | bool "umount -a option"
|
---|
| 473 | default n
|
---|
[1765] | 474 | depends on UMOUNT
|
---|
[821] | 475 | help
|
---|
| 476 | Support -a option to unmount all currently mounted filesystems.
|
---|
| 477 |
|
---|
| 478 | comment "Common options for mount/umount"
|
---|
[1765] | 479 | depends on MOUNT || UMOUNT
|
---|
[821] | 480 |
|
---|
[1765] | 481 | config FEATURE_MOUNT_LOOP
|
---|
[821] | 482 | bool "Support loopback mounts"
|
---|
| 483 | default n
|
---|
[1765] | 484 | depends on MOUNT || UMOUNT
|
---|
[821] | 485 | help
|
---|
| 486 | Enabling this feature allows automatic mounting of files (containing
|
---|
| 487 | filesystem images) via the linux kernel's loopback devices. The mount
|
---|
| 488 | command will detect you are trying to mount a file instead of a block
|
---|
| 489 | device, and transparently associate the file with a loopback device.
|
---|
| 490 | The umount command will also free that loopback device.
|
---|
| 491 |
|
---|
| 492 | You can still use the 'losetup' utility (to manually associate files
|
---|
[1765] | 493 | with loop devices) if you need to do something advanced, such as
|
---|
[821] | 494 | specify an offset or cryptographic options to the loopback device.
|
---|
| 495 | (If you don't want umount to free the loop device, use "umount -D".)
|
---|
| 496 |
|
---|
[1765] | 497 | config FEATURE_MTAB_SUPPORT
|
---|
[821] | 498 | bool "Support for the old /etc/mtab file"
|
---|
| 499 | default n
|
---|
[1765] | 500 | depends on MOUNT || UMOUNT
|
---|
[821] | 501 | help
|
---|
| 502 | Historically, Unix systems kept track of the currently mounted
|
---|
| 503 | partitions in the file "/etc/mtab". These days, the kernel exports
|
---|
| 504 | the list of currently mounted partitions in "/proc/mounts", rendering
|
---|
| 505 | the old mtab file obsolete. (In modern systems, /etc/mtab should be
|
---|
| 506 | a symlink to /proc/mounts.)
|
---|
| 507 |
|
---|
| 508 | The only reason to have mount maintain an /etc/mtab file itself is if
|
---|
| 509 | your stripped-down embedded system does not have a /proc directory.
|
---|
| 510 | If you must use this, keep in mind it's inherently brittle (for
|
---|
| 511 | example a mount under chroot won't update it), can't handle modern
|
---|
| 512 | features like separate per-process filesystem namespaces, requires
|
---|
| 513 | that your /etc directory be writeable, tends to get easily confused
|
---|
| 514 | by --bind or --move mounts, won't update if you rename a directory
|
---|
| 515 | that contains a mount point, and so on. (In brief: avoid.)
|
---|
| 516 |
|
---|
| 517 | About the only reason to use this is if you've removed /proc from
|
---|
| 518 | your kernel.
|
---|
| 519 |
|
---|
| 520 | endmenu
|
---|
| 521 |
|
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