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XtResolvePathname - search for a file using standard substitution
#include <X11/Intrinsic.h>
char * XtResolvePathname(Display *display, const char *type, const char
*filename, const char *suffix, const char *path, Substitution
substitutions, Cardinal num_substitutions, XtFilePredicate pred-
icate);
display Specifies the display to use to find the language for lan-
guage substitutions.
type
filename
suffix Specify values to substitute into the path.
path Specifies the list of file specifications, or NULL.
substitutions
Specifies a list of additional substitutions to make into
the path, or NULL.
num_substitutions
Specifies the number of entries in substitutions.
predicate Specifies a procedure called to judge each potential file
name, or NULL.
The substitutions specified by XtResolvePathname are determined from
the value of the language string retrieved by XtDisplayInitialize for
the specified display. To set the language for all applications spec-
ify "*xnlLanguage: lang" in the resource database. The format and con-
tent of the language string are implementation-defined. One suggested
syntax is to compose the language string of three parts: a "language
part", a "territory part" and a "codeset part". The manner in which
this composition is accomplished is implementation-defined and the
Intrinsics make no interpretation of the parts other than to use them
in substitutions as described below.
XtResolvePathname calls XtFindFile with the following substitutions in
addition to any passed by the caller and returns the value returned by
XtFindFile:
%N The value of the filename parameter, or the application's class
name if filename is NULL.
%T The value of the type parameter.
%S The value of the suffix parameter.
%L The language string associated with the specified display.
%l The language part of the display's language string.
%t The territory part of the display's language string.
%c The codeset part of the display's language string.
%C The customization string retrieved from the resource database
associated with display.
%D The value of the implementation-specific default path.
If a path is passed to XtResolvePathname, it will be passed along to
XtFindFile. If the path argument is NULL, the value of the XFILE-
SEARCHPATH environment variable will be passed to XtFindFile. If
XFILESEARCHPATH is not defined, an implementation-specific default path
will be used which contains at least 6 entries. These entries must
contain the following substitutions:
1. %C, %N, %S, %T, %L or %C, %N, %S, %T, %l, %t, %c
2. %C, %N, %S, %T, %l
3. %C, %N, %S, %T
4. %N, %S, %T, %L or %N, %S, %T, %l, %t, %c
5. %N, %S, %T, %l
6. %N, %S, %T
The order of these six entries within the path must be as given above.
The order and use of substitutions within a given entry is implementa-
tion dependent. If the path begins with a colon, it will be preceded
by %N%S. If the path includes two adjacent colons, %N%S will be
inserted between them.
The type parameter is intended to be a category of files, usually being
translated into a directory in the pathname. Possible values might
include "app-defaults", "help", and "bitmap".
The suffix parameter is intended to be appended to the file name. Pos-
sible values might include ".txt", ".dat", and ".bm".
A suggested value for the default path on POSIX-based systems is
/usr/lib/X11/%L/%T/%N%C%S:/usr/lib/X11/%l/%T/%N%C%S:\
/usr/lib/X11/%T/%N%C%S:/usr/lib/X11/%L/%T/%N%S:\
/usr/lib/X11/%l/%T/%N%S:/usr/lib/X11/%T/%N%S
Using this example, if the user has specified a language, it will be
used as a subdirectory of /usr/lib/X11 that will be searched for other
files. If the desired file is not found there, the lookup will be
tried again using just the language part of the specification. If the
file is not there, it will be looked for in /usr/lib/X11. The type
parameter is used as a subdirectory of the language directory or of
/usr/lib/X11, and suffix is appended to the file name.
The %D substitution allows the addition of path elements to the imple-
mentation-specific default path, typically to allow additional directo-
ries to be searched without preventing resources in the system directo-
ries from being found. For example, a user installing resource files
under a directory called "ourdir" might set XFILESEARCHPATH to
%D:ourdir/%T/%N%C:ourdir/%T/%N
The customization string is obtained by querying the resource database
currently associated with the display (the database returned by XrmGet-
Database) for the resource application_name.customization, class appli-
cation_class.Customization where application_name and application_class
are the values returned by XtGetApplicationNameAndClass. If no value
is specified in the database, the empty string is used.
It is the responsibility of the caller to free the returned string
using XtFree when it is no longer needed.
X Toolkit Intrinsics – C Language Interface
Xlib - C Language X Interface
X Version 11 libXt 1.1.5.2 XtResolvePathname(3)