[Buildroot] [git commit branch/2023.11.x] docs/manual: extend makedev syntax section
Peter Korsgaard
peter at korsgaard.com
Thu Feb 29 15:46:44 UTC 2024
commit: https://git.buildroot.net/buildroot/commit/?id=a9c5e028edb648de8a9ce355d93973dd6c95fbd7
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/2023.11.x
The section of the manual describing the makedev syntax is not
up-to-date with the current features, and does not properly describe
existing ones.
- extend the list of types with the requirements on the existence of
the target file or directory; for 'c', 'b', and 'p', the existence
requirement is inherited from mknod(2):
ERRORS
...
ENOENT A directory component in pathname does not exist or is a
dangling symbolic link.
for the other types, the existence requirements are extracted from
the source of makedev.c;
- format the types flags, so they are rendered in monospace;
- extend the 'mode' description, as it can be set to -1 for 'f', 'd',
or 'r', so that only the uid and gid are set. This is most useful
for 'r', where setting the same mode recursively for all the
sub-directories and files alike does not really make sense; indeed
in this case, the modes are usually set correctly when the package
(or rootfs overlay) installs the files, and only the uid and gid are
interesting to set;
- extend and update the examples to show-case the -1 mode use-case.
Signed-off-by: Yann E. MORIN <yann.morin at orange.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
(cherry picked from commit 738fb6dfa48b19f39e4a8df38ac9dcc0b37e0aa4)
Signed-off-by: Peter Korsgaard <peter at korsgaard.com>
---
docs/manual/makedev-syntax.adoc | 33 +++++++++++++++++++--------------
1 file changed, 19 insertions(+), 14 deletions(-)
diff --git a/docs/manual/makedev-syntax.adoc b/docs/manual/makedev-syntax.adoc
index d6efb31d42..e63c9233eb 100644
--- a/docs/manual/makedev-syntax.adoc
+++ b/docs/manual/makedev-syntax.adoc
@@ -22,14 +22,19 @@ There are a few non-trivial blocks:
- +name+ is the path to the file you want to create/modify
- +type+ is the type of the file, being one of:
- * f: a regular file
- * d: a directory
- * r: a directory recursively
- * c: a character device file
- * b: a block device file
- * p: a named pipe
+ * `f`: a regular file, which must already exist
+ * `F`: a regular file, which is ignored and not created if missing
+ * `d`: a directory, which is created, as well as its parents, if missing
+ * `r`: a directory recursively, which must already exist
+ * `c`: a character device file, which parent directory must exist
+ * `b`: a block device file, which parent directory must exist
+ * `p`: a named pipe, which parent directory must exist
- +mode+ are the usual permissions settings (only numerical values
- are allowed)
+ are allowed);
+ for type `d`, the mode of existing parents is not changed, but the mode
+ of created parents is set;
+ for types `f`, `F`, and `r`, +mode+ can also be set to +-1+ to not
+ change the mode (and only change uid and gid)
- +uid+ and +gid+ are the UID and GID to set on this file; can be
either numerical values or actual names
- +major+ and +minor+ are here for device files, set to +-+ for other
@@ -38,22 +43,22 @@ There are a few non-trivial blocks:
of files, and can be reduced to a loop, beginning at +start+,
incrementing its counter by +inc+ until it reaches +count+
-Let's say you want to change the permissions of a given file; using
-this syntax, you will need to write:
+Let's say you want to change the ownership and permissions of a given
+file; using this syntax, you will need to write:
----
/usr/bin/foo f 755 0 0 - - - - -
/usr/bin/bar f 755 root root - - - - -
/data/buz f 644 buz-user buz-group - - - - -
+/data/baz f -1 baz-user baz-group - - - - -
----
-Alternatively, if you want to change owner/permission of a directory
-recursively, you can write (to set UID to foo, GID to bar and access
-rights to rwxr-x--- for the directory /usr/share/myapp and all files
-and directories below it):
+Alternatively, if you want to change owner of a directory recursively,
+you can write (to set UID to `foo` and GID to `bar` for the directory
+`/usr/share/myapp` and all files and directories below it):
----
-/usr/share/myapp r 750 foo bar - - - - -
+/usr/share/myapp r -1 foo bar - - - - -
----
On the other hand, if you want to create the device file +/dev/hda+
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