[20] | 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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| 8 | config DMESG |
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| 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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| 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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| 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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| 49 | config FEATURE_FBSET_FANCY |
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| 50 | bool "Turn on extra fbset options" |
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| 51 | default n |
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| 52 | depends on FBSET |
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| 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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| 59 | config FEATURE_FBSET_READMODE |
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| 60 | bool "Turn on fbset readmode support" |
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| 61 | default n |
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| 62 | depends on FBSET |
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| 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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| 68 | config FDFLUSH |
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| 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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| 80 | config FDFORMAT |
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| 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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| 86 | config FDISK |
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| 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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| 98 | depends on FDISK |
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| 99 | help |
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| 100 | Enable this option to support large disks > 4GB. |
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| 101 | |
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| 102 | config FEATURE_FDISK_WRITABLE |
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| 103 | bool "Write support" |
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| 104 | default y |
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| 105 | depends on FDISK |
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| 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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| 111 | config FEATURE_AIX_LABEL |
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| 112 | bool "Support AIX disklabels" |
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| 113 | default n |
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| 114 | depends on FDISK && FEATURE_FDISK_WRITABLE |
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| 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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| 119 | config FEATURE_SGI_LABEL |
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| 120 | bool "Support SGI disklabels" |
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| 121 | default n |
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| 122 | depends on FDISK && FEATURE_FDISK_WRITABLE |
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| 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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| 127 | config FEATURE_SUN_LABEL |
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| 128 | bool "Support SUN disklabels" |
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| 129 | default n |
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| 130 | depends on FDISK && FEATURE_FDISK_WRITABLE |
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| 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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| 135 | config FEATURE_OSF_LABEL |
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| 136 | bool "Support BSD disklabels" |
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| 137 | default n |
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| 138 | depends on FDISK && FEATURE_FDISK_WRITABLE |
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| 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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| 143 | config FEATURE_FDISK_ADVANCED |
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| 144 | bool "Support expert mode" |
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| 145 | default n |
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| 146 | depends on FDISK && FEATURE_FDISK_WRITABLE |
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| 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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| 153 | config FREERAMDISK |
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| 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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| 164 | config FSCK_MINIX |
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| 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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| 175 | config MKFS_MINIX |
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| 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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| 184 | depends on FSCK_MINIX || MKFS_MINIX |
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| 185 | |
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| 186 | config FEATURE_MINIX2 |
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| 187 | bool "Support Minix fs v2 (fsck_minix/mkfs_minix)" |
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| 188 | default y |
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| 189 | depends on FSCK_MINIX || MKFS_MINIX |
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| 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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| 195 | config GETOPT |
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| 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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| 206 | config HEXDUMP |
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| 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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| 213 | config HWCLOCK |
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| 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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| 222 | config FEATURE_HWCLOCK_LONG_OPTIONS |
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| 223 | bool "Support long options (--hctosys,...)" |
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| 224 | default n |
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| 225 | depends on HWCLOCK && GETOPT_LONG |
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| 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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| 231 | config FEATURE_HWCLOCK_ADJTIME_FHS |
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| 232 | bool "Use FHS /var/lib/hwclock/adjtime" |
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| 233 | default y |
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| 234 | depends on HWCLOCK |
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| 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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| 243 | config IPCRM |
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| 244 | bool "ipcrm" |
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| 245 | default n |
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| 246 | select FEATURE_SUID |
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| 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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| 252 | config IPCS |
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| 253 | bool "ipcs" |
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| 254 | default n |
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| 255 | select FEATURE_SUID |
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| 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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| 260 | config LOSETUP |
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| 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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| 268 | config MDEV |
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| 269 | bool "mdev" |
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| 270 | default n |
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| 271 | help |
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| 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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| 274 | |
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| 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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| 278 | bool "Support /etc/mdev.conf" |
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| 279 | default n |
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| 280 | depends on MDEV |
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| 281 | help |
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| 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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| 284 | |
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| 285 | For more information, please see docs/mdev.txt |
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| 286 | |
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| 287 | config FEATURE_MDEV_EXEC |
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| 288 | bool "Support command execution at device addition/removal" |
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| 289 | default n |
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| 290 | depends on FEATURE_MDEV_CONF |
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| 291 | help |
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| 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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| 294 | |
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| 295 | For more information, please see docs/mdev.txt |
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| 296 | |
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| 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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| 303 | |
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| 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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| 307 | |
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| 308 | config MKSWAP |
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| 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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| 321 | config FEATURE_MKSWAP_V0 |
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| 322 | bool "version 0 support" |
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| 323 | default n |
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| 324 | depends on MKSWAP |
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| 325 | # depends on MKSWAP && DEPRECATED |
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| 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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| 331 | config MORE |
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| 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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| 341 | config FEATURE_USE_TERMIOS |
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| 342 | bool "Use termios to manipulate the screen" |
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| 343 | default y |
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| 344 | depends on MORE |
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| 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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| 352 | config MOUNT |
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| 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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| 363 | config FEATURE_MOUNT_NFS |
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| 364 | bool "Support mounting NFS file systems" |
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| 365 | default n |
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| 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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| 369 | help |
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| 370 | Enable mounting of NFS file systems. |
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| 371 | |
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| 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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| 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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| 408 | config RDATE |
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| 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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| 417 | config READPROFILE |
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| 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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| 423 | config SETARCH |
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| 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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| 432 | config SWAPONOFF |
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| 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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| 443 | config SWITCH_ROOT |
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| 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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| 462 | config UMOUNT |
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| 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, |
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| 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'. |
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| 470 | |
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| 471 | config FEATURE_UMOUNT_ALL |
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| 472 | bool "umount -a option" |
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| 473 | default n |
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| 474 | depends on UMOUNT |
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| 475 | help |
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| 476 | Support -a option to unmount all currently mounted filesystems. |
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| 477 | |
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| 478 | comment "Common options for mount/umount" |
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| 479 | depends on MOUNT || UMOUNT |
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| 480 | |
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| 481 | config FEATURE_MOUNT_LOOP |
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| 482 | bool "Support loopback mounts" |
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| 483 | default n |
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| 484 | depends on MOUNT || UMOUNT |
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| 485 | help |
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| 486 | Enabling this feature allows automatic mounting of files (containing |
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| 487 | filesystem images) via the linux kernel's loopback devices. The mount |
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| 488 | command will detect you are trying to mount a file instead of a block |
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| 489 | device, and transparently associate the file with a loopback device. |
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| 490 | The umount command will also free that loopback device. |
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| 491 | |
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| 492 | You can still use the 'losetup' utility (to manually associate files |
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| 493 | with loop devices) if you need to do something advanced, such as |
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| 494 | specify an offset or cryptographic options to the loopback device. |
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| 495 | (If you don't want umount to free the loop device, use "umount -D".) |
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| 496 | |
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| 497 | config FEATURE_MTAB_SUPPORT |
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| 498 | bool "Support for the old /etc/mtab file" |
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| 499 | default n |
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| 500 | depends on MOUNT || UMOUNT |
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| 501 | help |
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| 502 | Historically, Unix systems kept track of the currently mounted |
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| 503 | partitions in the file "/etc/mtab". These days, the kernel exports |
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| 504 | the list of currently mounted partitions in "/proc/mounts", rendering |
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| 505 | the old mtab file obsolete. (In modern systems, /etc/mtab should be |
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| 506 | a symlink to /proc/mounts.) |
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| 507 | |
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| 508 | The only reason to have mount maintain an /etc/mtab file itself is if |
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| 509 | your stripped-down embedded system does not have a /proc directory. |
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| 510 | If you must use this, keep in mind it's inherently brittle (for |
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| 511 | example a mount under chroot won't update it), can't handle modern |
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| 512 | features like separate per-process filesystem namespaces, requires |
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| 513 | that your /etc directory be writeable, tends to get easily confused |
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| 514 | by --bind or --move mounts, won't update if you rename a directory |
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| 515 | that contains a mount point, and so on. (In brief: avoid.) |
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| 516 | |
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| 517 | About the only reason to use this is if you've removed /proc from |
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| 518 | your kernel. |
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| 519 | |
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| 520 | endmenu |
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| 521 | |
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