NAME
XrmGetFileDatabase, XrmPutFileDatabase, XrmGetStringDatabase,
XrmLocaleOfDatabase, XrmGetDatabase, XrmSetDatabase, XrmDestroyDatabase
- retrieve and store resource databases
SYNTAX
XrmDatabase XrmGetFileDatabase(char *filename);
void XrmPutFileDatabase(XrmDatabase database, char *stored_db);
XrmDatabase XrmGetStringDatabase(char *data,
char *XrmLocaleOfDatabase(XrmDatabase database);
XrmDatabase XrmGetDatabase(Display *display);
void XrmSetDatabase(Display *display, XrmDatabase database);
void XrmDestroyDatabase(XrmDatabase database);
ARGUMENTS
filename Specifies the resource database file name.
database Specifies the database that is to be used.
stored_db Specifies the file name for the stored database.
data Specifies the database contents using a string.
database Specifies the resource database.
display Specifies the connection to the X server.
DESCRIPTION
The XrmGetFileDatabase function opens the specified file, creates a new
resource database, and loads it with the specifications read in from
the specified file. The specified file should contain a sequence of
entries in valid ResourceLine format (see section 15.1); the database
that results from reading a file with incorrect syntax is
implementation-dependent. The file is parsed in the current locale,
and the database is created in the current locale. If it cannot open
the specified file, XrmGetFileDatabase returns NULL.
The XrmPutFileDatabase function stores a copy of the specified database
in the specified file. Text is written to the file as a sequence of
entries in valid ResourceLine format (see section 15.1). The file is
written in the locale of the database. Entries containing resource
names that are not in the Host Portable Character Encoding or
containing values that are not in the encoding of the database locale,
are written in an implementation-dependent manner. The order in which
entries are written is implementation-dependent. Entries with
representation types other than ‘‘String’’ are ignored.
The XrmGetStringDatabase function creates a new database and stores the
resources specified in the specified null-terminated string.
XrmGetStringDatabase is similar to XrmGetFileDatabase except that it
reads the information out of a string instead of out of a file. The
string should contain a sequence of entries in valid ResourceLine
format (see section 15.1) terminated by a null character; the database
that results from using a string with incorrect syntax is
implementation-dependent. The string is parsed in the current locale,
and the database is created in the current locale.
If database is NULL, XrmDestroyDatabase returns immediately.
The XrmLocaleOfDatabase function returns the name of the locale bound
to the specified database, as a null-terminated string. The returned
locale name string is owned by Xlib and should not be modified or freed
by the client. Xlib is not permitted to free the string until the
database is destroyed. Until the string is freed, it will not be
modified by Xlib.
The XrmGetDatabase function returns the database associated with the
specified display. It returns NULL if a database has not yet been set.
The XrmSetDatabase function associates the specified resource database
(or NULL) with the specified display. The database previously
associated with the display (if any) is not destroyed. A client or
toolkit may find this function convenient for retaining a database once
it is constructed.
FILE SYNTAX
The syntax of a resource file is a sequence of resource lines
terminated by newline characters or the end of the file. The syntax of
an individual resource line is:
ResourceLine = Comment | IncludeFile | ResourceSpec | <empty line>
Comment = "!" {<any character except null or newline>}
IncludeFile = "#" WhiteSpace "include" WhiteSpace FileName WhiteSpace
FileName = <valid filename for operating system>
ResourceSpec = WhiteSpace ResourceName WhiteSpace ":" WhiteSpace Value
ResourceName = [Binding] {Component Binding} ComponentName
Binding = "." | "*"
WhiteSpace = {<space> | <horizontal tab>}
Component = "?" | ComponentName
ComponentName = NameChar {NameChar}
NameChar = "a"-"z" | "A"-"Z" | "0"-"9" | "_" | "-"
Value = {<any character except null or unescaped newline>}
Elements separated by vertical bar (|) are alternatives. Curly braces
({...}) indicate zero or more repetitions of the enclosed elements.
Square brackets ([...]) indicate that the enclosed element is optional.
Quotes ("...") are used around literal characters.
IncludeFile lines are interpreted by replacing the line with the
contents of the specified file. The word ‘‘include’’ must be in
lowercase. The file name is interpreted relative to the directory of
the file in which the line occurs (for example, if the file name
contains no directory or contains a relative directory specification).
If a ResourceName contains a contiguous sequence of two or more Binding
characters, the sequence will be replaced with single ‘‘.’’ character
if the sequence contains only ‘‘.’’ characters; otherwise, the sequence
will be replaced with a single ‘‘*’’ character.
A resource database never contains more than one entry for a given
ResourceName. If a resource file contains multiple lines with the same
ResourceName, the last line in the file is used.
Any white space characters before or after the name or colon in a
ResourceSpec are ignored. To allow a Value to begin with white space,
the two-character sequence ‘‘\space’’ (backslash followed by space) is
recognized and replaced by a space character, and the two-character
sequence ‘‘\tab’’ (backslash followed by horizontal tab) is recognized
and replaced by a horizontal tab character. To allow a Value to
contain embedded newline characters, the two-character sequence ‘‘\n’’
is recognized and replaced by a newline character. To allow a Value to
be broken across multiple lines in a text file, the two-character
sequence ‘‘\newline’’ (backslash followed by newline) is recognized and
removed from the value. To allow a Value to contain arbitrary
character codes, the four-character sequence ‘‘\nnn’’, where each n is
a digit character in the range of ‘‘0’’-‘‘7’’, is recognized and
replaced with a single byte that contains the octal value specified by
the sequence. Finally, the two-character sequence ‘‘\\’’ is recognized
and replaced with a single backslash.
SEE ALSO
XrmGetResource(3), XrmInitialize(3), XrmPutResource(3)
Xlib - C Language X Interface