X-Git-Url: https://review.fuel-infra.org/gitweb?a=blobdiff_plain;ds=sidebyside;f=cirros-testvm%2Fsrc-cirros%2Fbuildroot-2015.05%2Fpackage%2Fmakedevs%2FREADME;fp=cirros-testvm%2Fsrc-cirros%2Fbuildroot-2015.05%2Fpackage%2Fmakedevs%2FREADME;h=70844bf802c66c4c396c7152417b9d7c97bc2f78;hb=b0a0f15dfaa205161a7fcb20cf1b8cd4948c2ef3;hp=0000000000000000000000000000000000000000;hpb=c6ac3cd55ee2da956195eee393b0882105dfad4e;p=packages%2Ftrusty%2Fcirros-testvm.git diff --git a/cirros-testvm/src-cirros/buildroot-2015.05/package/makedevs/README b/cirros-testvm/src-cirros/buildroot-2015.05/package/makedevs/README new file mode 100644 index 0000000..70844bf --- /dev/null +++ b/cirros-testvm/src-cirros/buildroot-2015.05/package/makedevs/README @@ -0,0 +1,35 @@ +When building a target filesystem, it is desirable to not have to +become root and then run 'mknod' a thousand times. Using a device +table you can create device nodes and directories "on the fly". + +You can do all sorts of interesting things with a device table file. +For example, if you want to adjust the permissions on a particular +file you can just add an entry like: + + /sbin/foobar f 2755 0 0 - - - - - + +and (assuming the file /sbin/foobar exists) it will be made setuid +root (regardless of what its permissions are on the host filesystem. + +Furthermore, you can use a single table entry to create a many device +minors. For example, if I wanted to create /dev/hda and +/dev/hda[0-15] I could just use the following two table entries: + + /dev/hda b 640 0 0 3 0 0 0 - + /dev/hda b 640 0 0 3 1 1 1 15 + +Device table entries take the form of: + + + +where name is the file name, type can be one of: + + f: A regular file + d: Directory + c: Character special device file + b: Block special device file + p: Fifo (named pipe) + +uid is the user id for the target file, gid is the group id for the +target file. The rest of the entries (major, minor, etc) apply only +to device special files.