scons_gd/scons/doc/user/install.xml
2022-10-15 16:06:26 +02:00

346 lines
9.7 KiB
XML

<?xml version='1.0'?>
<!DOCTYPE sconsdoc [
<!ENTITY % scons SYSTEM "../scons.mod">
%scons;
<!ENTITY % builders-mod SYSTEM "../generated/builders.mod">
%builders-mod;
<!ENTITY % functions-mod SYSTEM "../generated/functions.mod">
%functions-mod;
<!ENTITY % tools-mod SYSTEM "../generated/tools.mod">
%tools-mod;
<!ENTITY % variables-mod SYSTEM "../generated/variables.mod">
%variables-mod;
]>
<chapter id="chap-install"
xmlns="http://www.scons.org/dbxsd/v1.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.scons.org/dbxsd/v1.0 http://www.scons.org/dbxsd/v1.0/scons.xsd">
<title>Installing Files in Other Directories: the &Install; Builder</title>
<!--
__COPYRIGHT__
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-->
<para>
Once a program is built,
it is often appropriate to install it in another
directory for public use.
You use the &Install; method
to arrange for a program, or any other file,
to be copied into a destination directory:
</para>
<scons_example name="install_ex1">
<file name="SConstruct" printme="1">
env = Environment()
hello = env.Program('hello.c')
env.Install('__ROOT__/usr/bin', hello)
</file>
<file name="hello.c">
int main() { printf("Hello, world!\n"); }
</file>
</scons_example>
<para>
Note, however, that installing a file is
still considered a type of file "build."
This is important when you remember that
the default behavior of &SCons; is
to build files in or below the current directory.
If, as in the example above,
you are installing files in a directory
outside of the top-level &SConstruct; file's directory tree,
you must specify that directory
(or a higher directory, such as <literal>/</literal>)
for it to install anything there:
</para>
<scons_output example="install_ex1" suffix="1">
<scons_output_command>scons -Q</scons_output_command>
<scons_output_command>scons -Q __ROOT__/usr/bin</scons_output_command>
</scons_output>
<para>
It can, however, be cumbersome to remember
(and type) the specific destination directory
in which the program (or other file)
should be installed. A call to &Default; can be used to
add the directory to the list of default targets,
removing the need to type it,
but sometimes you don't want to install on every build.
This is an area where the &Alias;
function comes in handy,
allowing you, for example,
to create a pseudo-target named <literal>install</literal>
that can expand to the specified destination directory:
</para>
<scons_example name="install_ex2">
<file name="SConstruct" printme="1">
env = Environment()
hello = env.Program('hello.c')
env.Install('__ROOT__/usr/bin', hello)
env.Alias('install', '__ROOT__/usr/bin')
</file>
<file name="hello.c">
int main() { printf("Hello, world!\n"); }
</file>
</scons_example>
<para>
This then yields the more natural
ability to install the program
in its destination as a separate
invocation, as follows:
</para>
<scons_output example="install_ex2" suffix="1">
<scons_output_command>scons -Q</scons_output_command>
<scons_output_command>scons -Q install</scons_output_command>
</scons_output>
<section>
<title>Installing Multiple Files in a Directory</title>
<para>
You can install multiple files into a directory
simply by calling the &Install; function multiple times:
</para>
<scons_example name="install_ex3">
<file name="SConstruct" printme="1">
env = Environment()
hello = env.Program('hello.c')
goodbye = env.Program('goodbye.c')
env.Install('__ROOT__/usr/bin', hello)
env.Install('__ROOT__/usr/bin', goodbye)
env.Alias('install', '__ROOT__/usr/bin')
</file>
<file name="hello.c">
int main() { printf("Hello, world!\n"); }
</file>
<file name="goodbye.c">
int main() { printf("Goodbye, world!\n"); }
</file>
</scons_example>
<para>
Or, more succinctly, listing the multiple input
files in a list
(just like you can do with any other builder):
</para>
<sconstruct>
env = Environment()
hello = env.Program('hello.c')
goodbye = env.Program('goodbye.c')
env.Install('__ROOT__/usr/bin', [hello, goodbye])
env.Alias('install', '__ROOT__/usr/bin')
</sconstruct>
<para>
Either of these two examples yields:
</para>
<scons_output example="install_ex3" suffix="1">
<scons_output_command>scons -Q install</scons_output_command>
</scons_output>
</section>
<section>
<title>Installing a File Under a Different Name</title>
<para>
The &Install; method preserves the name
of the file when it is copied into the
destination directory.
If you need to change the name of the file
when you copy it, use the &InstallAs; function:
</para>
<scons_example name="install_ex4">
<file name="SConstruct" printme="1">
env = Environment()
hello = env.Program('hello.c')
env.InstallAs('__ROOT__/usr/bin/hello-new', hello)
env.Alias('install', '__ROOT__/usr/bin')
</file>
<file name="hello.c">
int main() { printf("Hello, world!\n"); }
</file>
</scons_example>
<para>
This installs the <literal>hello</literal>
program with the name <literal>hello-new</literal>
as follows:
</para>
<scons_output example="install_ex4" suffix="1">
<scons_output_command>scons -Q install</scons_output_command>
</scons_output>
</section>
<section>
<title>Installing Multiple Files Under Different Names</title>
<para>
If you have multiple files that all
need to be installed with different file names,
you can either call the &InstallAs; function
multiple times, or as a shorthand,
you can supply same-length lists
for both the target and source arguments:
</para>
<scons_example name="install_ex5">
<file name="SConstruct" printme="1">
env = Environment()
hello = env.Program('hello.c')
goodbye = env.Program('goodbye.c')
env.InstallAs(['__ROOT__/usr/bin/hello-new',
'__ROOT__/usr/bin/goodbye-new'],
[hello, goodbye])
env.Alias('install', '__ROOT__/usr/bin')
</file>
<file name="hello.c">
int main() { printf("Hello, world!\n"); }
</file>
<file name="goodbye.c">
int main() { printf("Goodbye, world!\n"); }
</file>
</scons_example>
<para>
In this case, the &InstallAs; function
loops through both lists simultaneously,
and copies each source file into its corresponding
target file name:
</para>
<scons_output example="install_ex5" suffix="1">
<scons_output_command>scons -Q install</scons_output_command>
</scons_output>
</section>
<section>
<title>Installing a Shared Library</title>
<para>
If a shared library is created with the
&cv-link-SHLIBVERSION; variable set,
&scons; will create symbolic links as needed based on that
variable. To properly install such a library including the
symbolic links, use the &InstallVersionedLib; function.
</para>
<para>
For example, on a Linux system, this instruction:
</para>
<sconstruct>
foo = env.SharedLibrary(target="foo", source="foo.c", SHLIBVERSION="1.2.3")
</sconstruct>
<para>
Will produce a shared library
<filename>libfoo.so.1.2.3</filename>
and symbolic links
<filename>libfoo.so</filename> and
<filename>libfoo.so.1</filename>
which point to
<filename>libfoo.so.1.2.3</filename>.
You can use the Node returned by the &SharedLibrary;
builder in order to install the library and its
symbolic links in one go without having to list
them individually:
</para>
<sconstruct>
env.InstallVersionedLib(target="lib", source=foo)
</sconstruct>
<!-- didn't get this to illustrate what I expected: example reports
installing lib without version, while manual effort has it:
<scons_example name="install_ex6">
<file name="SConstruct" printme="1">
env = Environment()
foo = env.SharedLibrary(target="foo", source="foo.c", SHLIBVERSION="1.2.3")
ins = env.InstallVersionedLib(target="lib", source=foo)
env.Alias('install', ins)
</file>
<file name="foo.c">
int call_foo() {
printf("Hello world");
return(0);
}
</file>
</scons_example>
<scons_output example="install_ex6" suffix="1">
<scons_output_command>scons -Q install</scons_output_command>
</scons_output>
-->
<para>
On systems which expect a shared library to be installed both with
a name that indicates the version, for run-time resolution,
and as a plain name, for link-time resolution, the
&InstallVersionedLib; function can be used. Symbolic links
appropriate to the type of system will be generated based on
symlinks of the source library.
</para>
</section>
</chapter>