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author | Harald Sitter <sitter@kde.org> | 2019-03-15 11:39:46 +0100 |
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committer | Harald Sitter <sitter@kde.org> | 2019-03-26 12:57:41 +0100 |
commit | 998982a47cbc4ab8779c85a28052fb96195fd2a1 (patch) | |
tree | a2043cec8057868caf87c13a4a3b9f8ac1d77808 | |
parent | a3ed87ca7808363d8752f919617f88010ebf46b3 (diff) | |
download | kconfig-998982a47cbc4ab8779c85a28052fb96195fd2a1.tar.gz kconfig-998982a47cbc4ab8779c85a28052fb96195fd2a1.tar.bz2 |
point readme to the wiki page
Summary:
the wiki page says the readme is duplicated into the wiki.
so, what we end up with is either
- they end up out of sync
- someone gets real angry because the wiki needs format markup while the
readme must not have markup
- someone doesn't get angry and simply copies either markup or nomarkup to
the respectively unsuitable target
it's an unsustainable situation... so instead let's point the readme to
the wiki and consider that the place where the documentation is maintained
Subscribers: kde-frameworks-devel
Tags: #frameworks
Differential Revision: https://phabricator.kde.org/D19779
-rw-r--r-- | src/kconf_update/README.kconf_update | 253 |
1 files changed, 1 insertions, 252 deletions
diff --git a/src/kconf_update/README.kconf_update b/src/kconf_update/README.kconf_update index 72509286..1a97c9ea 100644 --- a/src/kconf_update/README.kconf_update +++ b/src/kconf_update/README.kconf_update @@ -1,252 +1 @@ -README kconf_update - -Version: 1.1 -Author: Waldo Bastian <bastian@kde.org>, <bastian@suse.com> - -What it does -============ - -kconf_update is a tool designed to update config files. Over time applications -sometimes need to rearrange the way configuration options are stored. Since -such an update shouldn't influence the configuration options that the user -has selected, the application must take care that the options stored in the -old way will still be honored. - -What used to happen is that the application looks up both the old and the -new configuration option and then decides which one to use. This method has -several drawbacks: -* The application may need to read more configuration files than strictly -needed, resulting in a slower startup. -* The application becomes bigger with code that will only be used once. - -kconf_update addresses these problems by offering a framework to update -configuration files without adding code to the application itself. - - -How it works -============ - -Applications can install so called "update files" under -$KDEDIR/share/apps/kconf_update. An update file has ".upd" as extension and -contains instructions for transferring/converting configuration information -from one place to another. - -Updating the configuration happens automatically, either when KDE gets started -or when kded detects a new update file in the above mentioned location. - -Update files are separated into sections. Each section has an Id. When a -section describing a configuration change has been applied, the Id will be -stored in the file "kconf_updaterc". This information is used to make sure -that a configuration update is only performed once. - -If you overwrite an existing update file with a new version that contains a -new section, only the update instructions from this extra section will be -performed. - -File format of the update file -============================== - -Empty lines or lines that start with '#' are considered comments. -Commas (,) are used to seperate fields and may not occur as part -of any field and all of the keywords are case-sensitive, i.e. you -cannot say "key" instead of "Key" for example. - -Starting from KDE Frameworks 5 make sure to put Version=5 before the first "Id=" otherwise the upd file -will be skipped and the config file will not be updated. - -For the rest the file is parsed and executed sequentially from top to bottom. -Each line can contain one entry. The following entries are recognized: - - -Id=<id> - -With <id> identifying the group of update entries that follows. Once a group -of entries have been applied, their <id> is stored and this group of entries -will not be applied again. - - -File=<oldfile>,<newfile> -File=<oldfile> - -Specifies that configuration information is read from <oldfile> and written -to <newfile>. If you only specify <oldfile>, the information is read from -as well as written to <oldfile>. Note that if the file does not exist -at the time kconf_update first checks, no related update will be performed -(script won't be run at all, etc.). - - -Script=<script>[,<interpreter>] - -All entries from <oldfile> are piped into <script>. The output of script -is used as new entries for <newfile>. Existing entries can be deleted by -adding lines with "# DELETE [group]key" in the output of the script. -To delete a whole group use "# DELETEGROUP [group]". - -<script> should be installed into $(kde_datadir)/kconf_update, or -kconf_update will not be able to find it. It's also possible to install -kconf_update applications in $(kde_bindir)/kconf_update_bin, which opens the -door to kconf_update applications that are written in C++ and use Qt's -powerful string API instead. - -If Script was issued after a "Group" command the behavior is slightly -different: -All entries from <oldfile>/<oldgroup> are piped into <script>. The output -of script is used as new entries for <newfile>/<newgroup>, unless a different -group is specified with "[group]". Existing entries can be deleted from -<oldgroup> by adding lines with "# DELETE key" in the output of the script. -To delete <oldgroup> use "# DELETEGROUP". - -<interpreter> can be something like "perl". - -It is also possible to have a Script without specifying <oldfile> or -<newfile>. In that case the script is run but it will not be fed any input -and its output will simply be discarded. - -ScriptArguments=<arguments> - -If specified, the arguments will be passed to <script>. -IMPORTANT: It has to be specified before Script=. - -Group=<oldgroup>,<newgroup> -Group=<oldgroup> - -Specifies that configuration information is read from the group <oldgroup> -and written to <newgroup>. If you only specify <oldgroup>, the information -is read from as well as written to <oldgroup>. You can use <default> to -specify keys that are not under any group. -A group may be written either as "group" or as "[group]". The latter syntax -makes it possible to specify subgroups: "[group][subgroup]". - -RemoveGroup=<oldgroup> - -Specifies that <oldgroup> is removed entirely. This can be used -to remove obsolete entries or to force a revert to default values. - -Options=<option1>, <option2>, .... - -With this entry you can specify options that apply to the next "Script", -"Key" or "AllKeys" entry (only to the first!). Possible options are: - -- "copy" Copy the configuration item instead of moving it. This means that - the configuration item will not be deleted from <oldfile>/<oldgroup>. - -- "overwrite" Normally, a configuration item is not moved if an item with the - new name already exists. When this option is specified the old - configuration item will overwrite any existing item. - - -Key=<oldkey>,<newkey> -Key=<oldkey> - -Specifies that configuration information is read from the key <oldkey> -and written to <newkey>. If you only specify <oldkey>, the information -is read from as well as written to <oldkey>. - - -AllKeys - -Specifies that all configuration information in the selected group should -be moved (All keys). - -AllGroups - -Specifies that all configuration information from all keys in ALL -groups should be moved. - - -RemoveKey=<oldkey> - -Specifies that <oldkey> is removed from the selected group. This can be used -to remove obsolete entries or to force a revert to default values. - - -Example update file -=================== - -# This is comment -Version=5 -Id=kde2.2 -File=kioslaverc,kio_httprc -Group=Proxy Settings -Key=NoProxyFor -Key=UseProxy -Key=httpProxy,Proxy -Group=Cache Settings,Cache -Key=MaxCacheSize -Key=UseCache -Group=UserAgent -AllKeys -RemoveGroup=KDE -# End of file - - -The above update file extracts config information from the file "kioslaverc" -and stores it into the file "kio_httprc". - -It reads the keys "NoProxyFor", "UseProxy" and "httpProxy" from the group -"Proxy Settings" in the "kioslaverc" file. If any of these options are present -they are written to the keys "NoProxyFor", "UseProxy" and "Proxy" (!) in -the group "Proxy Settings" in the "kio_httprc" file. - -It also reads the keys "MaxCacheSize" and "UseCache" from the group -"Cache Settings" in the "kioslaverc" file and writes this information to the -keys "MaxCacheSize" and "UseCache" in the group "Cache" (!) in the -"kio_httprc" file. - -Then it takes all keys in the "UserAgent" group of the file "kioslaverc" -and moves then to the "UserAgent" group in the "kio_httprc" file. - -Finally it removes the entire "KDE" group in the kioslaverc file. - - -Debugging and testing -===================== - -If you are developing a kconf_update script and want to test or debug it you -need to make sure kconf_update runs again after each of your changes. There -are a number of ways to achieve this. - -The easiest is to not install the kconf_update script in the first place, but -manually call it through a pipe. If you want to test the update script for -your application KHello's config file khellorc, you can test by using - - cat ~/.kde/share/config/khellorc | khello_conf_update.sh - -(assuming khello_conf_update.sh is the kconf_update script and ~/.kde is your -$KDEHOME). This is easier than making install every time, but has the obvious -downside that you need to 'parse' your script's output yourself instead of -letting kconf_update do it and check the resulting output file. - -After 'make install' the kconf_update script is run by kded, but it does so -only once. This is of course the idea behind it, but while developing it can -be a problem. You can increase the revision number for each subsequent run -of 'make install' to force a new kconf_update run, but there's a better -approach that doesn't skyrocket the version number for a mediocre debug -session. - -kded doesn't really ignore scripts that it has already run right away. -Instead it checks the affected config file every time a .upd file is added -or changed. The reason it still doesn't run again on your config file lies -in the traces kconf_update leaves behind: it adds a special config group -'[$Version]' with a key 'update_info'. This key lists all kconf_update -scripts that have already been run on this config file. It also adds a group -for the script to $KDEHOME/share/config/kconf_updaterc. Just remove your -script entries from both your rcfile and kconf_updaterc, 'make install', -and kconf_update will happily run your script again, without you having to -increase the version number. - -If you want to know what kconf_update has been up to lately, have a look -at $KDEHOME/share/apps/kconf_update/log/update.log - - -Common Problems -=============== - -* kconf_update refuses to update an entry -If you change the value of an entry without changing the key or file, -make sure to tell kconf_update that it should overwrite the old entry -by adding "Options=overwrite". - - -Have fun, -Waldo +https://techbase.kde.org/Development/Tools/Using_kconf_update |