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-rw-r--r--system/doc/design_principles/release_handling.xml44
-rw-r--r--system/doc/design_principles/release_structure.xml20
2 files changed, 40 insertions, 24 deletions
diff --git a/system/doc/design_principles/release_handling.xml b/system/doc/design_principles/release_handling.xml
index 8ed36f3c56..4378b6599c 100644
--- a/system/doc/design_principles/release_handling.xml
+++ b/system/doc/design_principles/release_handling.xml
@@ -178,13 +178,13 @@
<marker id="instr"></marker>
<title>Release Handling Instructions</title>
<p>OTP supports a set of <em>release handling instructions</em>
- that is used when creating <c>.appup</c> files. The release
+ that are used when creating <c>.appup</c> files. The release
handler understands a subset of these, the <em>low-level</em>
instructions. To make it easier for the user, there are also a
number of <em>high-level</em> instructions, which are translated
to low-level instructions by <c>systools:make_relup</c>.</p>
<p>Here, some of the most frequently used instructions are
- described. The complete list of instructions is found in
+ described. The complete list of instructions can be found in
<c>appup(4)</c>.</p>
<p>First, some definitions:</p>
<taglist>
@@ -239,9 +239,10 @@
<p><c>update</c> with argument <c>supervisor</c> is used when
changing the start specification of a supervisor. See
<seealso marker="appup_cookbook#sup">Appup Cookbook</seealso>.</p>
- <p>The release handler finds the processes <em>using</em> a module
- to update by traversing the supervision tree of each running
- application and checking all the child specifications:</p>
+ <p>When a module is to be updated, the release handler finds
+ which processes that are <em>using</em> the module by
+ traversing the supervision tree of each running application
+ and checking all the child specifications:</p>
<code type="none">
{Id, StartFunc, Restart, Shutdown, Type, Modules}</code>
<p>A process is using a module if the name is listed in
@@ -265,8 +266,8 @@
<p>The instruction loads the module and is absolutely necessary
when running Erlang in embedded mode. It is not strictly
required when running Erlang in interactive (default) mode,
- since the code server automatically searches for and loads
- unloaded modules.</p>
+ since the code server then automatically searches for and
+ loads unloaded modules.</p>
<p>The opposite of <c>add_module</c> is <c>delete_module</c> which
unloads a module:</p>
<code type="none">
@@ -294,7 +295,7 @@
the modules are unloaded using a number of <c>delete_module</c>
instructions and then the application specification is unloaded
from the application controller.</p>
- <p>Instruction for removing an application:</p>
+ <p>Instruction for restarting an application:</p>
<code type="none">
{restart_application, Application}</code>
<p>Restarting an application means that the application is stopped
@@ -331,17 +332,17 @@
of the emulator and the core applications. Then it shuts down
the current emulator by calling <c>init:reboot()</c>, see
<c>init(3)</c>. All processes are terminated gracefully and
- the system can then be rebooted by the heart program, using
- the temporary boot file. After the reboot, the rest of the
- relup instructions are executed. This is done as a part of the
- boot script.</p>
+ the system is rebooted by the heart program, using the
+ temporary boot file. After the reboot, the rest of the relup
+ instructions are executed. This is done as a part of the
+ temporary boot script.</p>
<p>An info report is written when the upgrade is completed. To
programatically find out if the upgrade is complete,
- call <c>release_handler:which_releases/0</c> and check if the
- expected release has status <c>current</c>.</p>
- <p>The new version must be made permanent when the new emulator
- is up and running. Otherwise, the old version will be used in
- case of a new system reboot.</p>
+ call <c>release_handler:which_releases(current)</c> and check
+ if it returns the expected (i.e. the new) release.</p>
+ <p>The new release version must be made permanent when the new
+ emulator is up and running. Otherwise, the old version will be
+ used in case of a new system reboot.</p>
<p>On UNIX, the release handler tells the heart program which
command to use to reboot the system. Note that the environment
variable <c>HEART_COMMAND</c>, normally used by the heart
@@ -362,8 +363,8 @@
a relup script, and it shall always be placed at the end. If
the relup is generated by <c>systools:make_relup/3,4</c> this
is automatically ensured.</p>
- <p>When the release handler encounters the instruction, it shuts down
- the emulator by calling <c>init:reboot()</c>, see
+ <p>When the release handler encounters the instruction, it shuts
+ down the emulator by calling <c>init:reboot()</c>, see
<c>init(3)</c>. All processes are terminated gracefully and
the system can then be rebooted by the heart program using the
new release version. No more upgrade instruction will be
@@ -581,8 +582,8 @@ release_handler:remove_release(Vsn) => ok</code>
[].</code>
<p>2) Start the system as a simple target system. Note that in
reality, it should be started as an embedded system. However,
- using <c>erl</c> with the correct boot script and <c>.config</c>
- file is enough for illustration purposes:</p>
+ using <c>erl</c> with the correct boot script and config file is
+ enough for illustration purposes:</p>
<pre>
% <input>cd $ROOT</input>
% <input>bin/erl -boot $ROOT/releases/A/start -config $ROOT/releases/A/sys</input>
@@ -617,6 +618,7 @@ lib/ch_app-2/ebin/ch3.beam
releases/B/start.boot
releases/B/relup
releases/B/sys.config
+releases/B/ch_rel-2.rel
releases/ch_rel-2.rel</code>
<p>4) Copy the release package <c>ch_rel-2.tar.gz</c> to
the <c>$ROOT/releases</c> directory.</p>
diff --git a/system/doc/design_principles/release_structure.xml b/system/doc/design_principles/release_structure.xml
index 2e1daa611a..8aea0e1a10 100644
--- a/system/doc/design_principles/release_structure.xml
+++ b/system/doc/design_principles/release_structure.xml
@@ -4,7 +4,7 @@
<chapter>
<header>
<copyright>
- <year>2003</year><year>2009</year>
+ <year>2003</year><year>2011</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -61,12 +61,14 @@
{ApplicationN, AppVsnN}]}.</code>
<p>The file must be named <c>Rel.rel</c>, where <c>Rel</c> is a
unique name.</p>
- <p><c>Name</c>, <c>Vsn</c> and <c>Evsn</c> are strings.</p>
+ <p><c>Name</c>, <c>Vsn</c> and <c>EVsn</c> are strings.</p>
<p>Each <c>Application</c> (atom) and <c>AppVsn</c> (string) is
the name and version of an application included in the release.
- Note the the minimal release based on Erlang/OTP consists of
+ Note that the minimal release based on Erlang/OTP consists of
the <c>kernel</c> and <c>stdlib</c> applications, so these
applications must be included in the list.</p>
+ <p>If the release is to be upgraded, it must also include
+ the <c>sasl</c> application.</p>
<marker id="ch_rel"></marker>
<p>Example: We want to make a release of <c>ch_app</c> from
the <seealso marker="applications#ch_app">Applications</seealso>
@@ -173,6 +175,7 @@ lib/ch_app-1/ebin/ch_app.beam
lib/ch_app-1/ebin/ch_sup.beam
lib/ch_app-1/ebin/ch3.beam
releases/A/start.boot
+releases/A/ch_rel-1.rel
releases/ch_rel-1.rel</pre>
<p>Note that a new boot script was generated, without
the <c>local</c> option set, before the release package was made.
@@ -180,6 +183,17 @@ releases/ch_rel-1.rel</pre>
under <c>lib</c>. Also, we do not know where the release package
will be installed, so we do not want any hardcoded absolute paths
in the boot script here.</p>
+ <p>The release resource file <c>mysystem.rel</c> is duplicated in
+ the tar file. Originally, this file was only stored in
+ the <c>releases</c> directory in order to make it possible for
+ the <c>release_handler</c> to extract this file
+ separately. After unpacking the tar file, <c>release_handler</c>
+ would automatically copy the file
+ to <c>releases/FIRST</c>. However, sometimes the tar file is
+ unpacked without involving the <c>release_handler</c> (e.g. when
+ unpacking the first target system) and therefore the file is now
+ instead duplicated in the tar file so no manual copying is
+ necessary.</p>
<p>If a <c>relup</c> file and/or a system configuration file called
<c>sys.config</c> is found, these files are included in
the release package as well. See