The FindFile
function searches for a file in a list of directories.
If there is only one directory, it can be given as a simple string.
The function returns a File node if a matching file exists,
or None if no file is found.
(See the documentation for the Glob
function for an alternative way
of searching for entries in a directory.)
# one directory print("%s"%FindFile('missing', '.')) t = FindFile('exists', '.') print("%s %s"%(t.__class__, t))
% scons -Q
None
<class 'SCons.Node.FS.File'> exists
scons: `.' is up to date.
# several directories includes = [ '.', 'include', 'src/include'] headers = [ 'nonesuch.h', 'config.h', 'private.h', 'dist.h'] for hdr in headers: print('%-12s: %s'%(hdr, FindFile(hdr, includes)))
% scons -Q
nonesuch.h : None
config.h : config.h
private.h : src/include/private.h
dist.h : include/dist.h
scons: `.' is up to date.
If the file exists in more than one directory, only the first occurrence is returned.
print(FindFile('multiple', ['sub1', 'sub2', 'sub3'])) print(FindFile('multiple', ['sub2', 'sub3', 'sub1'])) print(FindFile('multiple', ['sub3', 'sub1', 'sub2']))
% scons -Q
sub1/multiple
sub2/multiple
sub3/multiple
scons: `.' is up to date.
In addition to existing files, FindFile
will also find derived files
(that is, non-leaf files) that haven't been built yet.
(Leaf files should already exist, or the build will fail!)
# Neither file exists, so build will fail Command('derived', 'leaf', 'cat >$TARGET $SOURCE') print(FindFile('leaf', '.')) print(FindFile('derived', '.'))
% scons -Q
leaf
derived
cat > derived leaf
# Only 'leaf' exists Command('derived', 'leaf', 'cat >$TARGET $SOURCE') print(FindFile('leaf', '.')) print(FindFile('derived', '.'))
% scons -Q
leaf
derived
cat > derived leaf
If a source file exists, FindFile
will correctly return the name
in the build directory.
# Only 'src/leaf' exists VariantDir('build', 'src') print(FindFile('leaf', 'build'))
% scons -Q
build/leaf
scons: `.' is up to date.