Update README

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Gregory Nutt 2015-04-15 11:31:13 -06:00
parent 688558c99a
commit 84fcc41a63

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@ -1,8 +1,8 @@
apps/system/zoninfo/README.txt
Author: Gregory Nutt <gnutt@nuttx.org>
Contents
=======
Directory Contents
==================
This directory contains logic to create a version of the TZ/Olson database.
This database is required if localtime() support is selected via
@ -18,17 +18,17 @@ Creating and Mounting a ROMFS TZ Database
=========================================
The ROMFS filesystem image can that be mounted during the boot-up sequence
so that it is available for the localtime logic. There are two steps to
so that it is available for the localtime() logic. There are two steps to
doing this:
- First, a ROM disk device must be created. This is done by calling
the function romdisk_register() as described in
nuttx/include/nuttx/fs/ramdisk.h. This is an OS level operation
and must be done in the board-level logic before your appliction
and must be done in the board-level logic before your application
starts.
romdisk_register() will create a block driver at /dev/ramN where N
is the device minor number that was provdied to romdisk_regsiter.
is the device minor number that was provided to romdisk_regsiter.
- The second step is to mount the file system. This step can be
performed either in your board configuration logic or by your
@ -57,8 +57,24 @@ modifications to the configuration that I used for testing:
CONFIG_SYSTEM_ZONEINFO=y
CONFIG_SYSTEM_ZONEINFO_ROMFS=y
Here is a sample run. I have not seen any errors but neither am I
certain that everything is working properly:
NOTE: The full TZ database is quite large. To create a reasonable sized
ROMFS image, I had to trim some of the files like this:
make context
cd ../apps/system/zoneinfo/tzbin/etc/zoneinfo
Remove as many timezone files as you can. Do not remove the GMT, localtime,
or posixrules files. Those might be needed in any event. Then you can
force rebuilding of the ROMFS filesystem be removing some files:
cd ../../..
rm romfs_zoneinfo.*
rm *.o
cd ../../nuttx
make
Here is a sample run. I have not seen any errors in single stepping through
the logic but neither am I certain that everything is working properly:
NuttShell (NSH)
nsh> date