From Linux Man Pages
xrdb - X server resource database utility
xrdb [-option ...] [filename]
DESCRIPTION
Xrdb is used to get or set the contents of the RESOURCE_MANAGER property on the root window of screen 0, or the
SCREEN_RESOURCES property on the root window of any or all screens, or everything combined. You would normally
run this program from your X startup file.
Most X clients use the RESOURCE_MANAGER and SCREEN_RESOURCES properties to get user preferences about color,
fonts, and so on for applications. Having this information in the server (where it is available to all clients)
instead of on disk, solves the problem in previous versions of X that required you to maintain defaults files on
every machine that you might use. It also allows for dynamic changing of defaults without editing files.
The RESOURCE_MANAGER property is used for resources that apply to all screens of the display. The
SCREEN_RESOURCES property on each screen specifies additional (or overriding) resources to be used for that
screen. (When there is only one screen, SCREEN_RESOURCES is normally not used, all resources are just placed in
the RESOURCE_MANAGER property.)
The file specified by filename (or the contents from standard input if - or no filename is given) is optionally
passed through the C preprocessor with the following symbols defined, based on the capabilities of the server
being used:
SERVERHOST=hostname
the hostname portion of the display to which you are connected.
SRVR_name
the SERVERHOST hostname string turned into a legal identifier. For example, "my-dpy.lcs.mit.edu" becomes
SRVR_my_dpy_lcs_mit_edu.
HOST=hostname
the same as SERVERHOST.
DISPLAY_NUM=num
the number of the display on the server host.
CLIENTHOST=hostname
the name of the host on which xrdb is running.
CLNT_name
the CLIENTHOST hostname string turned into a legal identifier. For example, "expo.lcs.mit.edu" becomes
CLNT_expo_lcs_mit_edu.
RELEASE=num
the vendor release number for the server. The interpretation of this number will vary depending on VEN-
DOR.
REVISION=num
the X protocol minor version supported by this server (currently 0).
VERSION=num
the X protocol major version supported by this server (should always be 11).
VENDOR="vendor"
a string literal specifying the vendor of the server.
VNDR_name
the VENDOR name string turned into a legal identifier. For example, "MIT X Consortium" becomes
VNDR_MIT_X_Consortium.
EXT_name
A symbol is defined for each protocol extension supported by the server. Each extension string name is
turned into a legal identifier. For example, "X3D-PEX" becomes EXT_X3D_PEX.
NUM_SCREENS=num
the total number of screens.
SCREEN_NUM=num
the number of the current screen (from zero).
BITS_PER_RGB=num
the number of significant bits in an RGB color specification. This is the log base 2 of the number of
distinct shades of each primary that the hardware can generate. Note that it usually is not related to
PLANES.
CLASS=visualclass
one of StaticGray, GrayScale, StaticColor, PseudoColor, TrueColor, DirectColor. This is the visual class
of the root window.
CLASS_visualclass=visualid
the visual class of the root window in a form you can #ifdef on. The value is the numeric id of the
visual.
COLOR defined only if CLASS is one of StaticColor, PseudoColor, TrueColor, or DirectColor.
CLASS_visualclass_depth=num
A symbol is defined for each visual supported for the screen. The symbol includes the class of the
visual and its depth; the value is the numeric id of the visual. (If more than one visual has the same
class and depth, the numeric id of the first one reported by the server is used.)
HEIGHT=num
the height of the root window in pixels.
WIDTH=num
the width of the root window in pixels.
PLANES=num
the number of bit planes (the depth) of the root window.
X_RESOLUTION=num
the x resolution of the screen in pixels per meter.
Y_RESOLUTION=num
the y resolution of the screen in pixels per meter.
SRVR_name, CLNT_name, VNDR_name, and EXT_name identifiers are formed by changing all characters other than let-
ters and digits into underscores (_).
Lines that begin with an exclamation mark (!) are ignored and may be used as comments.
Note that since xrdb can read from standard input, it can be used to the change the contents of properties
directly from a terminal or from a shell script.
OPTIONS
xrdb program accepts the following options:
-help This option (or any unsupported option) will cause a brief description of the allowable options and
parameters to be printed.
-display display
This option specifies the X server to be used; see X(7). It also specifies the screen to use for the
-screen option, and it specifies the screen from which preprocessor symbols are derived for the -global
option.
-all This option indicates that operation should be performed on the screen-independent resource property
(RESOURCE_MANAGER), as well as the screen-specific property (SCREEN_RESOURCES) on every screen of the
display. For example, when used in conjunction with -query, the contents of all properties are output.
For -load, -override and -merge, the input file is processed once for each screen. The resources which
occur in common in the output for every screen are collected, and these are applied as the screen-inde-
pendent resources. The remaining resources are applied for each individual per-screen property. This
the default mode of operation.
-global This option indicates that the operation should only be performed on the screen-independent RESOURCE_MAN-
AGER property.
-screen This option indicates that the operation should only be performed on the SCREEN_RESOURCES property of the
default screen of the display.
-screens
This option indicates that the operation should be performed on the SCREEN_RESOURCES property of each
screen of the display. For -load, -override and -merge, the input file is processed for each screen.
-n This option indicates that changes to the specified properties (when used with -load, -override or
-merge) or to the resource file (when used with -edit) should be shown on the standard output, but should
not be performed.
-quiet This option indicates that warning about duplicate entries should not be displayed.
-cpp filename
This option specifies the pathname of the C preprocessor program to be used. Although xrdb was designed
to use CPP, any program that acts as a filter and accepts the -D, -I, and -U options may be used.
-nocpp This option indicates that xrdb should not run the input file through a preprocessor before loading it
into properties.
-symbols
This option indicates that the symbols that are defined for the preprocessor should be printed onto the
standard output.
-query This option indicates that the current contents of the specified properties should be printed onto the
standard output. Note that since preprocessor commands in the input resource file are part of the input
file, not part of the property, they won't appear in the output from this option. The -edit option can
be used to merge the contents of properties back into the input resource file without damaging preproces-
sor commands.
-load This option indicates that the input should be loaded as the new value of the specified properties,
replacing whatever was there (i.e. the old contents are removed). This is the default action.
-override
This option indicates that the input should be added to, instead of replacing, the current contents of
the specified properties. New entries override previous entries.
-merge This option indicates that the input should be merged and lexicographically sorted with, instead of
replacing, the current contents of the specified properties.
-remove This option indicates that the specified properties should be removed from the server.
-retain This option indicates that the server should be instructed not to reset if xrdb is the first client.
This never be necessary under normal conditions, since xdm and xinit always act as the first client.
-edit filename
This option indicates that the contents of the specified properties should be edited into the given file,
replacing any values already listed there. This allows you to put changes that you have made to your
defaults back into your resource file, preserving any comments or preprocessor lines.
-backup string
This option specifies a suffix to be appended to the filename used with -edit to generate a backup file.
-Dname[=value]
This option is passed through to the preprocessor and is used to define symbols for use with conditionals
such as
-Uname This option is passed through to the preprocessor and is used to remove any definitions of this symbol.
-Idirectory
This option is passed through to the preprocessor and is used to specify a directory to search for files
that are referenced with #include.
FILES
Generalizes ~/.Xdefaults files.
RELATED
X(7), appres(1x), listres(1x), Xlib Resource Manager documentation, Xt resource documentation
ENVIRONMENT
DISPLAY to figure out which display to use.
BUGS
The default for no arguments should be to query, not to overwrite, so that it is consistent with other programs.
CATEGORY