Maemo Wiki Mirror - User contributions [en]

User:Tanner

2010-06-12T21:13:52Z

178.165.143.5: /* full optification */

= Packages =

info about some of the packages I've uploaded to extras-devel

== [http://maemo.org/packages/view/debhelper7/ debhelper7] ==

see also http://wiki.maemo.org/Packaging

A backport of Debhelper 7 for Fremantle is available in extras-devel.
It works transparently and can coexist with debhelper 5 in the SDK.
It also works on the autobuilder, if you specify
Build-Depends: debhelper7
in debian/control.
The following lines in debian/rules are necessary to use it:

PATH:=/usr/bin/dh7:/usr/bin:$(PATH)
export PATH
SBOX_REDIRECT_IGNORE=/usr/bin/perl
export SBOX_REDIRECT_IGNORE

We are working on enhancement to make optification is easier, i.e. direct installation of files in the /opt hierarchy.

If you also need a more recent cdbs, then use the package [http://maemo.org/packages/view/cdbs-dh7/ cdbs-dh7],
which conflicts with the standard cdbs and does not work on autobuilder yet.

To replace several tools in scratchbox you can also use the following line as a template
SBOX_REDIRECT_IGNORE:=$(shell echo /usr/bin/{perl,dh_*} | sed "s/ /:/g")

== CLI icon ==

For your convenience I have uuencoded Tim Samoff's [http://lists.maemo.org/pipermail/maemo-community/2010-January/003870.html CLI icon]
which is supposed to be added to the debian/control file of CLI apps. You can download it [http://maemory.com/N900/tools/cli.icon.txt here].

== [http://maemo.org/packages/view/kernel-flasher-maemo/ custom Linux kernel] ==

My custom kernel which contains probably everything one could need on the N900:

This custom kernel contains additional modules for IPv6, packet filtering,
NAT, tunneling, kernel configuration, Wifi mesh networking,
ext4, XFS, reiserfs, NTFS reading, NILFS2, ISO9660, UDF, CIFS, automounter,
UNIONFS, device mapper and dmloop, cryptography, cryptoloop,
EFI partitions, UTF8 codepages, mouse+joystick input,
USB/IP and generic USB device drivers.
It shows a boot logo.

Just install the package "kernel-flasher-maemo" from extras-devel/non-free (section System) and reboot.
Reverting to the original kernel is simple: "apt-get install --reinstall kernel kernel-flasher" or reflash only the original kernel image.
see [http://talk.maemo.org/showthread.php?t=43420 TMO page] for more details.

== GNU tools ==
the crippled busybox is installed on the N900.
command line users prefer the real GNU tools.
these are the optified packages for the device.
Most of them do not take use more RAM than busybox (a few KBs)!
[http://maemo.org/packages/view/coreutils-gnu/ coreutils-gnu]
[http://maemo.org/packages/view/diffutils-gnu/ diffutils-gnu]
[http://maemo.org/packages/view/findutils-gnu/ findutils-gnu]
[http://maemo.org/packages/view/grep-gnu/ grep-gnu]
[http://maemo.org/packages/view/sed-gnu/ sed-gnu]
[http://maemo.org/packages/view/tar-gnu/ tar-gnu]

== [http://maemo.org/packages/view/texlive-latex-base/ TeXLive 2009] ==
[http://talk.maemo.org/showthread.php?t=42087 talk page]

== [http://maemo.org/packages/view/r-base-core/ R] (statistics) ==

bug: installation fails with ucfr missing
solution: wait or edit r-base-core.postinst and comment line 44 out

== [http://maemo.org/packages/view/libblas3gf/ BLAS] [http://maemo.org/packages/view/liblapack3gf/ LAPACK] [http://maemo.org/packages/view/libsuitesparse-3.1.0/ suitesparse] ==

bug: linking against BLAS and LAPACK currently hardcodes the links found in the -dev package.

== [http://maemo.org/packages/view/python-numpy/ numpy], [http://maemo.org/packages/view/python-scipy/ scipy], [http://maemo.org/packages/view/python-sympy/ sympy] ==

[http://talk.maemo.org/showthread.php?t=33020 some discussion]

== [http://maemo.org/packages/view/bonnie++/ bonnie++] (filesystem benchmarks) ==
see [http://talk.maemo.org/showpost.php?p=504332&postcount=76 post and ff]

== [http://maemo.org/packages/view/tcl8.5/ tcl8.5] [http://maemo.org/packages/view/tk8.5/ tk8.5] [http://maemo.org/packages/view/python-tk/ python-tk] ==

== [http://maemo.org/packages/view/lzma/ lzma] and its successor [http://maemo.org/packages/view/xz-utils/ xz-utils] ==

an extremely efficient compressor. it is much faster than bzip2 for decompression and yields about 30% smaller files.

== [http://maemo.org/packages/view/xskat/ xskat] ==

bug: keyboard doesn't work.
bug: window close button is not visible

== experimental packages ==

some experimental ports which I have not yet uploaded to extras-devel can be found in my repository

deb http://www.maemory.com/N900/ fremantle free incompatible

currently: python2.6, perl5.10, GNU compiler collection 4.4.3, autoconf 2.64, automake1.10

----

= Ideas/plans: =

== [https://garage.maemo.org/projects/moebian/ Moebian]: Maemo/MeeGo on Debian ==

[http://wiki.maemo.org/Maemo_on_Debian Wiki] and [http://talk.maemo.org/showthread.php?t=44967 discussion]

== Brainstorm: [https://maemo.org/community/brainstorm/view/more_efficient_and_flexible_use_of_internal_flash Repartitioning] ==

[http://talk.maemo.org/showthread.php?t=37869 brainstorm discussion]
[http://talk.maemo.org/showthread.php?t=35122 repartitioning thread]

== Brainstorm: [http://maemo.org/community/brainstorm/view/stylus_and_finger_friendly_uis/ Stylus and finger friendly UIs] ==

[http://talk.maemo.org/showthread.php?p=525854 brainstorm discussion]

== alternative USB host solution ==

[http://talk.maemo.org/showthread.php?t=41870 USB/IP]

== full [http://wiki.maemo.org/Opt_Problem optification] ==

Ideally addon software should be installed only in /opt without any symlinks in / (NAND)
in accordance with [http://www.pathname.com/fhs/2.2/fhs-3.12.html FHS].
/usr/local should be moved and symlinked to /opt/local and is reserved for own programs not maintained by dpkg.

A package may either install its files directly (for small packages) in the /opt/maemo hierarchy (bin,etc,lib,man,share)
or in a separate directory /opt/<package> with its own hierarchy (bin,etc,lib,man,share).
For the latter solution packages should symlink all non-private files to /opt/maemo/{bin,etc,lib,man,share}
and the search paths of Maemo need to be adjusted in /etc/profile and /etc/osso-af-init/af-defines.sh:

* PATH=$PATH:/opt/maemo/bin (and sbin for root)
* ld.so.conf: add /opt/maemo/lib
* locales: [https://bugs.maemo.org/show_bug.cgi?id=8363 LOCPATH]=LOCPATH=/usr/share/locale:/opt/maemo/share/locale
* MANPATH=/opt/maemo/share/man
* pkgconfig: /usr/share/pkgconfig:/opt/maemo/share/pkgconfig
* info in info?: /usr/share/info:/opt/maemo/share/info
* apps in hildon: [https://bugs.maemo.org/show_bug.cgi?id=10531 Bug about Application Menu] /usr/share/applications:/opt/maemo/share/applications
* icons in hildon ?: /usr/share/icons:/opt/maemo/share/icons
this list may be incomplete - please help to complete it

As NAND is much faster than eMMC a cache manager could mantain a list
of very often used binaries and libraries in /opt and automatically
copy them and symlink them to a fixed size cache in NAND.

TMPDIR=/var/tmp should be moved to /opt/tmp
or /var/opt should symlink to /opt/var and contain a larger tmp directory.

A package for Maemo (tested on N800) that allows a package to set environment variables like XDG_DATA_DIRS is available: [http://svn.nomike.org/playground/trunk/opt-support/ opt-support]. I propose packages depend on opt-support and in their postinst add their variables to the file "/etc/profile.env". -- dannym

== chroot instead of /opt ==
I have described my currently preferred [http://maemo.org/community/brainstorm/view/remove_256mb_limitation_of_the_rootfs_partition_in_the_n900/ solution as #5]
----

= Tips and tricks: =

== fresh builds ==

[http://maemo.org/packages/repository/latest/fremantle_extras-devel_free_armel/all/ latest packages]

[https://garage.maemo.org/builder/fremantle/?C=M;O=D autobuilder current builds]

== [[Repartitioning the flash]] ==

[http://talk.maemo.org/showpost.php?p=424811&postcount=66 how to swap FAT and ext3 parition]
[http://talk.maemo.org/showpost.php?p=425359&postcount=68 how to implement USB mass storage with a loopback file]

== Setting up a repository mirror on your server ==

[http://www.maemory.com/mirror/repro-maemo.tgz reprepro configuration]

== Safely free some space on rootfs ==

[http://maemory.com/N900/tools/moveroot.sh This script] shows you how much space is freed.
It can also detect whether some directories have already been moved.
WARNING: Although this script works for most users, you should always perform a backup before running it.
Do not use this script if you have already used some other methods or scripts from [[Free_up_rootfs_space]]!
In this case reflashing is recommended.

# install the rootsh package from extras
# download the [http://maemory.com/N900/tools/moveroot.sh script] to your MyDocs (or upload it via SSH)
# in Terminal run
sudo gainroot
sh /home/user/MyDocs/moveroot.sh

It should have freed about 95MB on your rootfs.
Upgrading the firmware OTA after using the script is supposed to work.
If you reflash the firmware the script will automatically remove the files from the old firmware
when you run it again.

[http://maemory.com/N900/tools/unmoveroot.sh This untested script] reverts the modifications and moves as many as possible files back to rootfs.
Make sure that you have enough space on rootfs for that. Otherwise it will abort the operation. Instructions are the same as for moveroot.sh,
except that you call unmoveroot.sh.

== On-device flashing of a custom kernel image ==

This how to flash a kernel on-device (without USB/flasher 3.5):

# you have a kernel image /path/zImage (with it's modules installed)
# install the package "sdk-fiasco-gen" from SDK
# become root: "sudo gainroot"
# make a "fiasco" :)
fiasco-gen -o /path/zImage.fiasco -g -k /path/zImage
# flash it
/sbin/fiasco-image-update /path/zImage.fiasco

== Reflashing & Restore ==

this is a slightly modified version of the script I use to restore my N900 after a reflash.
My reflashing procedure is:

# store all settings with Backup on my SD card
# reflash with standard http://wiki.maemo.org/Updating_the_firmware, i.e.
sudo flasher-3.5 -F ''<current firmware image>''.bin -f -R
# restore old backup except programs
# install rootsh from System
# in Terminal:
sudo sh /home/backup/restore.sh
with [http://maemory.com/N900/tools/restore.sh this script (for PR<1.2] or [http://maemory.com/N900/tools/restore1.2.sh this script (PR1.2)] in /home/backup (feedback and patches are welcome).
It expects that you made a backup of /root and your selected modified files (e.g. /etc/ssh) in /home/backup.
The file "pkgs" should contain a list (line by line) of the package names you want to install.

User:Tanner

2010-06-12T21:12:55Z

178.165.143.5: /* full optification */

= Packages =

info about some of the packages I've uploaded to extras-devel

== [http://maemo.org/packages/view/debhelper7/ debhelper7] ==

see also http://wiki.maemo.org/Packaging

A backport of Debhelper 7 for Fremantle is available in extras-devel.
It works transparently and can coexist with debhelper 5 in the SDK.
It also works on the autobuilder, if you specify
Build-Depends: debhelper7
in debian/control.
The following lines in debian/rules are necessary to use it:

PATH:=/usr/bin/dh7:/usr/bin:$(PATH)
export PATH
SBOX_REDIRECT_IGNORE=/usr/bin/perl
export SBOX_REDIRECT_IGNORE

We are working on enhancement to make optification is easier, i.e. direct installation of files in the /opt hierarchy.

If you also need a more recent cdbs, then use the package [http://maemo.org/packages/view/cdbs-dh7/ cdbs-dh7],
which conflicts with the standard cdbs and does not work on autobuilder yet.

To replace several tools in scratchbox you can also use the following line as a template
SBOX_REDIRECT_IGNORE:=$(shell echo /usr/bin/{perl,dh_*} | sed "s/ /:/g")

== CLI icon ==

For your convenience I have uuencoded Tim Samoff's [http://lists.maemo.org/pipermail/maemo-community/2010-January/003870.html CLI icon]
which is supposed to be added to the debian/control file of CLI apps. You can download it [http://maemory.com/N900/tools/cli.icon.txt here].

== [http://maemo.org/packages/view/kernel-flasher-maemo/ custom Linux kernel] ==

My custom kernel which contains probably everything one could need on the N900:

This custom kernel contains additional modules for IPv6, packet filtering,
NAT, tunneling, kernel configuration, Wifi mesh networking,
ext4, XFS, reiserfs, NTFS reading, NILFS2, ISO9660, UDF, CIFS, automounter,
UNIONFS, device mapper and dmloop, cryptography, cryptoloop,
EFI partitions, UTF8 codepages, mouse+joystick input,
USB/IP and generic USB device drivers.
It shows a boot logo.

Just install the package "kernel-flasher-maemo" from extras-devel/non-free (section System) and reboot.
Reverting to the original kernel is simple: "apt-get install --reinstall kernel kernel-flasher" or reflash only the original kernel image.
see [http://talk.maemo.org/showthread.php?t=43420 TMO page] for more details.

== GNU tools ==
the crippled busybox is installed on the N900.
command line users prefer the real GNU tools.
these are the optified packages for the device.
Most of them do not take use more RAM than busybox (a few KBs)!
[http://maemo.org/packages/view/coreutils-gnu/ coreutils-gnu]
[http://maemo.org/packages/view/diffutils-gnu/ diffutils-gnu]
[http://maemo.org/packages/view/findutils-gnu/ findutils-gnu]
[http://maemo.org/packages/view/grep-gnu/ grep-gnu]
[http://maemo.org/packages/view/sed-gnu/ sed-gnu]
[http://maemo.org/packages/view/tar-gnu/ tar-gnu]

== [http://maemo.org/packages/view/texlive-latex-base/ TeXLive 2009] ==
[http://talk.maemo.org/showthread.php?t=42087 talk page]

== [http://maemo.org/packages/view/r-base-core/ R] (statistics) ==

bug: installation fails with ucfr missing
solution: wait or edit r-base-core.postinst and comment line 44 out

== [http://maemo.org/packages/view/libblas3gf/ BLAS] [http://maemo.org/packages/view/liblapack3gf/ LAPACK] [http://maemo.org/packages/view/libsuitesparse-3.1.0/ suitesparse] ==

bug: linking against BLAS and LAPACK currently hardcodes the links found in the -dev package.

== [http://maemo.org/packages/view/python-numpy/ numpy], [http://maemo.org/packages/view/python-scipy/ scipy], [http://maemo.org/packages/view/python-sympy/ sympy] ==

[http://talk.maemo.org/showthread.php?t=33020 some discussion]

== [http://maemo.org/packages/view/bonnie++/ bonnie++] (filesystem benchmarks) ==
see [http://talk.maemo.org/showpost.php?p=504332&postcount=76 post and ff]

== [http://maemo.org/packages/view/tcl8.5/ tcl8.5] [http://maemo.org/packages/view/tk8.5/ tk8.5] [http://maemo.org/packages/view/python-tk/ python-tk] ==

== [http://maemo.org/packages/view/lzma/ lzma] and its successor [http://maemo.org/packages/view/xz-utils/ xz-utils] ==

an extremely efficient compressor. it is much faster than bzip2 for decompression and yields about 30% smaller files.

== [http://maemo.org/packages/view/xskat/ xskat] ==

bug: keyboard doesn't work.
bug: window close button is not visible

== experimental packages ==

some experimental ports which I have not yet uploaded to extras-devel can be found in my repository

deb http://www.maemory.com/N900/ fremantle free incompatible

currently: python2.6, perl5.10, GNU compiler collection 4.4.3, autoconf 2.64, automake1.10

----

= Ideas/plans: =

== [https://garage.maemo.org/projects/moebian/ Moebian]: Maemo/MeeGo on Debian ==

[http://wiki.maemo.org/Maemo_on_Debian Wiki] and [http://talk.maemo.org/showthread.php?t=44967 discussion]

== Brainstorm: [https://maemo.org/community/brainstorm/view/more_efficient_and_flexible_use_of_internal_flash Repartitioning] ==

[http://talk.maemo.org/showthread.php?t=37869 brainstorm discussion]
[http://talk.maemo.org/showthread.php?t=35122 repartitioning thread]

== Brainstorm: [http://maemo.org/community/brainstorm/view/stylus_and_finger_friendly_uis/ Stylus and finger friendly UIs] ==

[http://talk.maemo.org/showthread.php?p=525854 brainstorm discussion]

== alternative USB host solution ==

[http://talk.maemo.org/showthread.php?t=41870 USB/IP]

== full [http://wiki.maemo.org/Opt_Problem optification] ==

Ideally addon software should be installed only in /opt without any symlinks in / (NAND)
in accordance with [http://www.pathname.com/fhs/2.2/fhs-3.12.html FHS].
/usr/local should be moved and symlinked to /opt/local and is reserved for own programs not maintained by dpkg.

A package may either install its files directly (for small packages) in the /opt/maemo hierarchy (bin,etc,lib,man,share)
or in a separate directory /opt/<package> with its own hierarchy (bin,etc,lib,man,share).
For the latter solution packages should symlink all non-private files to /opt/maemo/{bin,etc,lib,man,share}
and the search paths of Maemo need to be adjusted in /etc/profile and /etc/osso-af-init/af-defines.sh:

* PATH=$PATH:/opt/maemo/usr/bin (and sbin for root)
* ld.so.conf: add /opt/maemo/usr/lib
* locales: [https://bugs.maemo.org/show_bug.cgi?id=8363 LOCPATH]=LOCPATH=/usr/share/locale:/opt/maemo/usr/share/locale
* MANPATH=/opt/maemo/usr/share/man
* pkgconfig: /usr/share/pkgconfig:/opt/maemo/share/pkgconfig
* info in info?: /usr/share/info:/opt/maemo/share/info
* apps in hildon: [https://bugs.maemo.org/show_bug.cgi?id=10531 Bug about Application Menu] /usr/share/applications:/opt/maemo/usr/share/applications
* icons in hildon ?: /usr/share/icons:/opt/maemo/usr/share/icons
this list may be incomplete - please help to complete it

As NAND is much faster than eMMC a cache manager could mantain a list
of very often used binaries and libraries in /opt and automatically
copy them and symlink them to a fixed size cache in NAND.

TMPDIR=/var/tmp should be moved to /opt/tmp
or /var/opt should symlink to /opt/var and contain a larger tmp directory.

A package for Maemo (tested on N800) that allows a package to set environment variables like XDG_DATA_DIRS is available: [http://svn.nomike.org/playground/trunk/opt-support/ opt-support]. I propose packages depend on opt-support and in their postinst add their variables to the file "/etc/profile.env". -- dannym

== chroot instead of /opt ==
I have described my currently preferred [http://maemo.org/community/brainstorm/view/remove_256mb_limitation_of_the_rootfs_partition_in_the_n900/ solution as #5]
----

= Tips and tricks: =

== fresh builds ==

[http://maemo.org/packages/repository/latest/fremantle_extras-devel_free_armel/all/ latest packages]

[https://garage.maemo.org/builder/fremantle/?C=M;O=D autobuilder current builds]

== [[Repartitioning the flash]] ==

[http://talk.maemo.org/showpost.php?p=424811&postcount=66 how to swap FAT and ext3 parition]
[http://talk.maemo.org/showpost.php?p=425359&postcount=68 how to implement USB mass storage with a loopback file]

== Setting up a repository mirror on your server ==

[http://www.maemory.com/mirror/repro-maemo.tgz reprepro configuration]

== Safely free some space on rootfs ==

[http://maemory.com/N900/tools/moveroot.sh This script] shows you how much space is freed.
It can also detect whether some directories have already been moved.
WARNING: Although this script works for most users, you should always perform a backup before running it.
Do not use this script if you have already used some other methods or scripts from [[Free_up_rootfs_space]]!
In this case reflashing is recommended.

# install the rootsh package from extras
# download the [http://maemory.com/N900/tools/moveroot.sh script] to your MyDocs (or upload it via SSH)
# in Terminal run
sudo gainroot
sh /home/user/MyDocs/moveroot.sh

It should have freed about 95MB on your rootfs.
Upgrading the firmware OTA after using the script is supposed to work.
If you reflash the firmware the script will automatically remove the files from the old firmware
when you run it again.

[http://maemory.com/N900/tools/unmoveroot.sh This untested script] reverts the modifications and moves as many as possible files back to rootfs.
Make sure that you have enough space on rootfs for that. Otherwise it will abort the operation. Instructions are the same as for moveroot.sh,
except that you call unmoveroot.sh.

== On-device flashing of a custom kernel image ==

This how to flash a kernel on-device (without USB/flasher 3.5):

# you have a kernel image /path/zImage (with it's modules installed)
# install the package "sdk-fiasco-gen" from SDK
# become root: "sudo gainroot"
# make a "fiasco" :)
fiasco-gen -o /path/zImage.fiasco -g -k /path/zImage
# flash it
/sbin/fiasco-image-update /path/zImage.fiasco

== Reflashing & Restore ==

this is a slightly modified version of the script I use to restore my N900 after a reflash.
My reflashing procedure is:

# store all settings with Backup on my SD card
# reflash with standard http://wiki.maemo.org/Updating_the_firmware, i.e.
sudo flasher-3.5 -F ''<current firmware image>''.bin -f -R
# restore old backup except programs
# install rootsh from System
# in Terminal:
sudo sh /home/backup/restore.sh
with [http://maemory.com/N900/tools/restore.sh this script (for PR<1.2] or [http://maemory.com/N900/tools/restore1.2.sh this script (PR1.2)] in /home/backup (feedback and patches are welcome).
It expects that you made a backup of /root and your selected modified files (e.g. /etc/ssh) in /home/backup.
The file "pkgs" should contain a list (line by line) of the package names you want to install.

Documentation/Maemo 5 Developer Guide/Packaging, Deploying and Distributing/Installing under opt and MyDocs

2010-06-12T20:14:07Z

178.165.143.5: /* /opt as a good alternative */

The N900 has about 100MB of free space in the root file system partition. This is not very much and would fill up quite quickly when installing additional applications. As a workaround, the <code>/opt</code> directory has been linked to a different partition with more space (about 1 GB) and <code>/home/user/MyDocs</code> is also available in certain cases, with even more space (about 25 GB). Developers are encouraged to make good use of them, specially for applications requiring more than 500KB, including dependencies.

== /opt as a good alternative ==

The <code>/opt</code> directory is on an ext3 partition that is permanently mounted. Users cannot mess with it by accident. Of course, not everything needs to be moved to <code>/opt</code>: configuration files are best left in <code>/etc</code>, for example, and there is no point in moving small files like the various <code>*.desktop</code> and <code>*.service</code> files (except for the fact that automake's "configure --prefix=/opt" moves them there whether you want to or not).

The maemo-optify tool helps developers to prepare Debian packages that use <code>/opt</code>. This tool moves selected files inside the package to locations under <code>/opt</code>, and will symbolically link from the original location to the new place of the file. It is available on [http://gitorious.org/maemo-af/maemo-optify gitorious] as well as in [http://maemo.org/packages/view/maemo-optify/ Extras-devel].

The [[Uploading_to_Extras-devel#Autobuilder_special_considerations|Autobuilder]] supports automatic optification of submitted packages via maemo-optify. It is triggered by the file "<code>debian/optify</code>", as described in the [http://gitorious.org/maemo-af/maemo-optify/blobs/master/README README].

== Considering /home/user/MyDocs ==

The <code>/home/user/MyDocs</code> directory is another candidate for large collections of data files included in applications such as game graphics or maps. Using <code>/opt</code> is mostly transparent to package maintainers and end-users, but <code>/home/user/MyDocs</code> needs more careful consideration.

The <code>/home/user/MyDocs</code> partition uses VFAT as its filesystem (which has some limitations compared to ext3) and it is removable: it will be unmounted and exported over USB when the user plugs in the cable. Also, <code>/home/user/MyDocs</code> is visible in the File manager. This all means:

* Be aware that VFAT is not really a POSIX filesystem. Things like symbolic links, permission bits, and so on, will not work as nicely as they do on a real POSIX filesystem.
* Be prepared that your files are not there at all while the partition is unmounted. Do not prevent the partition from being unmounted because you keep some of the files open.
* User might see your files, can get confused and try to delete or rename them.

In summary, you cannot really put programs, libraries or theme graphics into <code>/home/user/MyDocs</code>. Instead, use <code>/opt</code> for these.

[[Category:Development]]
[[Category:Documentation]]
[[Category:Fremantle]]

Documentation/Maemo 5 Developer Guide/Packaging, Deploying and Distributing/Installing under opt and MyDocs

2010-06-12T20:13:38Z

178.165.143.5: /* /opt as a good alternative */

The N900 has about 100MB of free space in the root file system partition. This is not very much and would fill up quite quickly when installing additional applications. As a workaround, the <code>/opt</code> directory has been linked to a different partition with more space (about 1 GB) and <code>/home/user/MyDocs</code> is also available in certain cases, with even more space (about 25 GB). Developers are encouraged to make good use of them, specially for applications requiring more than 500KB, including dependencies.

== /opt as a good alternative ==

The <code>/opt</code> directory is on an ext3 partition that is permanently mounted. Users cannot mess with it by accident. Of course, not everything needs to be moved to <code>/opt</code>: configuration files are best left in <code>/etc</code>, for example, and there is no point in moving small files like the various <code>*.desktop</code> and <code>*.service</code> files (except for the fact that automake configure --prefix moves them there whether you want to or not).

The maemo-optify tool helps developers to prepare Debian packages that use <code>/opt</code>. This tool moves selected files inside the package to locations under <code>/opt</code>, and will symbolically link from the original location to the new place of the file. It is available on [http://gitorious.org/maemo-af/maemo-optify gitorious] as well as in [http://maemo.org/packages/view/maemo-optify/ Extras-devel].

The [[Uploading_to_Extras-devel#Autobuilder_special_considerations|Autobuilder]] supports automatic optification of submitted packages via maemo-optify. It is triggered by the file "<code>debian/optify</code>", as described in the [http://gitorious.org/maemo-af/maemo-optify/blobs/master/README README].

== Considering /home/user/MyDocs ==

The <code>/home/user/MyDocs</code> directory is another candidate for large collections of data files included in applications such as game graphics or maps. Using <code>/opt</code> is mostly transparent to package maintainers and end-users, but <code>/home/user/MyDocs</code> needs more careful consideration.

The <code>/home/user/MyDocs</code> partition uses VFAT as its filesystem (which has some limitations compared to ext3) and it is removable: it will be unmounted and exported over USB when the user plugs in the cable. Also, <code>/home/user/MyDocs</code> is visible in the File manager. This all means:

* Be aware that VFAT is not really a POSIX filesystem. Things like symbolic links, permission bits, and so on, will not work as nicely as they do on a real POSIX filesystem.
* Be prepared that your files are not there at all while the partition is unmounted. Do not prevent the partition from being unmounted because you keep some of the files open.
* User might see your files, can get confused and try to delete or rename them.

In summary, you cannot really put programs, libraries or theme graphics into <code>/home/user/MyDocs</code>. Instead, use <code>/opt</code> for these.

[[Category:Development]]
[[Category:Documentation]]
[[Category:Fremantle]]

Documentation/Maemo 5 Developer Guide/Packaging, Deploying and Distributing/Installing under opt and MyDocs

2010-06-12T20:13:09Z

178.165.143.5: /* /opt as a good alternative */

The N900 has about 100MB of free space in the root file system partition. This is not very much and would fill up quite quickly when installing additional applications. As a workaround, the <code>/opt</code> directory has been linked to a different partition with more space (about 1 GB) and <code>/home/user/MyDocs</code> is also available in certain cases, with even more space (about 25 GB). Developers are encouraged to make good use of them, specially for applications requiring more than 500KB, including dependencies.

== /opt as a good alternative ==

The <code>/opt</code> directory is on an ext3 partition that is permanently mounted. Users cannot mess with it by accident. Of course, not everything needs to be moved to <code>/opt</code>: configuration files are best left in <code>/etc</code>, for example, and there is no point in moving small files like the various <code>*.desktop</code> and <code>*.service</code> files (except for the fact that automake --prefix moves them there whether you want to or not).

The maemo-optify tool helps developers to prepare Debian packages that use <code>/opt</code>. This tool moves selected files inside the package to locations under <code>/opt</code>, and will symbolically link from the original location to the new place of the file. It is available on [http://gitorious.org/maemo-af/maemo-optify gitorious] as well as in [http://maemo.org/packages/view/maemo-optify/ Extras-devel].

The [[Uploading_to_Extras-devel#Autobuilder_special_considerations|Autobuilder]] supports automatic optification of submitted packages via maemo-optify. It is triggered by the file "<code>debian/optify</code>", as described in the [http://gitorious.org/maemo-af/maemo-optify/blobs/master/README README].

== Considering /home/user/MyDocs ==

The <code>/home/user/MyDocs</code> directory is another candidate for large collections of data files included in applications such as game graphics or maps. Using <code>/opt</code> is mostly transparent to package maintainers and end-users, but <code>/home/user/MyDocs</code> needs more careful consideration.

The <code>/home/user/MyDocs</code> partition uses VFAT as its filesystem (which has some limitations compared to ext3) and it is removable: it will be unmounted and exported over USB when the user plugs in the cable. Also, <code>/home/user/MyDocs</code> is visible in the File manager. This all means:

* Be aware that VFAT is not really a POSIX filesystem. Things like symbolic links, permission bits, and so on, will not work as nicely as they do on a real POSIX filesystem.
* Be prepared that your files are not there at all while the partition is unmounted. Do not prevent the partition from being unmounted because you keep some of the files open.
* User might see your files, can get confused and try to delete or rename them.

In summary, you cannot really put programs, libraries or theme graphics into <code>/home/user/MyDocs</code>. Instead, use <code>/opt</code> for these.

[[Category:Development]]
[[Category:Documentation]]
[[Category:Fremantle]]