1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
|
# LibraryCheck
Determine whether a shared library is available to be loaded by Raku
## Synopsis
```raku
use LibraryCheck;
if !library-exists('sndfile', v1) {
die "Cannot load libsndfile";
}
```
## Description
This module provides a mechanism that will determine whether a named
shared library is available and can be used by NativeCall.
It exports a single function `library-exists` that returns a boolean to
indicate whether the named shared library can be loaded and used. The
library name should be supplied without any (OS-dependent) "lib" prefix
and no extension (for example, `'crypt'` for `libcrypt.so`).
This can be used in a builder to determine whether a module has a chance
of working (and possibly aborting the build), or in tests to cause the
tests that may rely on a missing library to be skipped.
The second positional argument is a [Version](Version) object that
indicates the version of the library that is required, it defaults to
`v1`, if you don't care which version exists then it possible to pass a
new Version object without any version parts (i.e., `Version.new()`).
Many systems require that the version is specified, so if portability is
a concern, an actual version number should be given.
If the `:exception` adverb is passed to `library-exists` then an
exception (`X::NoLibrary`) will be thrown if the library isn't available
rather than returning `False`. So the case above can be more simply
written as:
```raku
library-check('sndfile', v1, :exception);
```
The implementation is somewhat of a hack currently and definitely
shouldn't be taken as an example of nice Raku code.
## Installation
Assuming you have a working Rakudo installation you should be able to
install this with *zef*:
# From the source directory
zef install .
# Remote installation
zef install LibraryCheck
Other install mechanisms may be become available in the future.
## Support
Suggestions/patches are welcomed via github at https://github.com/jonathanstowe/LibraryCheck/issues
I'd be particularly interested in having it work properly on all the platforms that rakudo will work on.
## Licence
Please see the [LICENCE](LICENCE) file in the distribution.
© Jonathan Stowe 2015 - 2021
|
