GUM v.1.0.0

A

Gimp start flags and rc-files

Most of the time Gimp is probably started by an icon or a menu in your favorite window manager but you can also start it by hand. There are also several initiation files that control the behavior of Gimp.

Gimp command line switches aka flags (options)

A excellent source of information about the command line switches and environments that Gimp support is found in the Gimp man page. It's located in the doc dir in your Gimp source distribution and normally you only have to type man gimp after you have installed Gimp.

We will make a short description of each flag here in GUM. All of this is done in a shell, for example in an xterm window or rxvt window. As we mentioned earlier, you have probably hidden all this in your Window manager so you only have to click on a icon or drag at a menu. If you want to test flags and different environments or even run gimp without Xwindow you must do this in a shell.

Typing gimp --help or gimp -h and press enter will result in a short description of available flags that you can give Gimp.

[olof@olof olof]$ gimp --help 
Usage: gimp [option ...] [files ...]
Valid options are:
  -h --help              Output this help.
  -v --version           Output version info.
  -b --batch <commands>  Run in batch mode.
  -n --no-interface      Run without a user interface.
  --no-data              Do not load patterns, gradients, palettes, brushes.
  --verbose              Show startup messages.
  --no-splash            Do not show the startup window.
  --no-splash-image      Do not add an image to the startup window.
  --no-shm               Do not use shared memory between GIMP and its plugins.
  --no-xshm              Do not use the X Shared Memory extension.
  --display <display>    Use the designated X display.
[olof@olof olof]$

The -h and --help flags obviously printed out the above message. The -v and --version flags shows what version of Gimp you are running (this information is also available in the about dialog and the splash window that shows up when you start Gimp). It will typically look like this:

[olof@olof olof]$ gimp -v
GIMP version 1.0

Always visit www.gimp.org or ftp.gimp.org or one of it's mirrors to get the newest stable version of Gimp.

Batch mode and "no-interface"

The -b and --batch option allows you to execute Gimp with arguments to run. This is ideal if you want to execute a lot commands to a lot of files. Then its can be quite annoying to have a GUI to do it in (i.e. open image, apply commands, save image, open another image, apply command etc., you see it will be a lot of mouse training if you want to do this). The <command> is a script-fu that will do the actual work for you (even if you can execute ordinary gimp pdb command directly)

The -n and --no-interface are suitable if you run Gimp in batch mode since you most of the time don't want to have a user interface if you are running a batch. This will also save some memory and system resources, so it would be quite pointless to fire up the user interface. Here is an example of two batch commands

gimp -n -b '(gimp-procedural-db-dump "pdb_dump.tmp")' '(gimp-quit 0)'

which will dump Gimp's pdb database to a file called pdb_dump.tmp in your working directory. Here is a example of a custom script that is invoked by Gimp (my-script is your own personal custom script).

gimp -n -b '(my-script 1 "\"Sample text.\"")' '(gimp-quit 0)'

The (gimp-quit 0) is so Gimp quits gracefully and returns the command prompt to you.

If you don't have Xwindow up and running (i.e you are running your UNIX session in a console that has no graphic capabilities or you have a modem connection to your UNIX host with a vt100 terminal only), then you still can run Gimp in batch mode, just do it like this:

Xvfb :1 -screen 0 10x10x8 -pixdepths 1 &
gimp --display :1.0 -n -b '<commandos> ' '(gimp-quit 0)'

This will fire up an invisible X server, which you run Gimp in.

More options

As you saw above, we introduced a new flag --display, since X lets you run Gimp on one host and displaying it on another, you have to specify the display to run Gimp's user interface on.

Normally you run and display Gimp on the same host, and you don't have to barter about display settings. We will give you an example on how to use the display option in Gimp. Say that you have a "Supercomputer" at your campus running UNIX and this computer has Gimp installed. Then it would be more than efficient to edit huge Gimp images at this computer while displaying them at your local workstation or X-terminal. Here is a quick how to do it. At your workstation, you will have to execute a command allowing the Supercomputer to display Gimp on your workstation.

[olof@olof olof]$ xhost niceriver.frozenriver.com (my local supercomputer ;)
niceriver.frozenriver.com being added to access control list

The second line tells us that we have enabled the "supercomputer" to access our X-server at our workstation. All we have to do now is to telnet or rlogin or rsh to the "supercomputer"

[olof@olof olof]$ rlogin niceriver.frozenriver.com
[olof@niceriver olof]$

Now we are logged in to the "supercomputer". All we have to is to fire off Gimp and tell it where to display, i.e at olof.frozenriver.com, and which display to use at olof.frozenriver.com. Since we only have one display at olof we will use display number 0

gimp --no-xshm --display olof.frozenriver.com:0.0

Now Gimp will display at your workstation and you can work with it just like you would have if you had run Gimp at your workstation. When you are finished with Gimp you just have to logout from the supercomputer and tell your workstation that you don't want the supercomputer accessing your X-server

[olof@olof olof]$ xhost - niceriver.frozenriver.com
niceriver.frozenriver.com being removed from access control list

The last line tells us that the supercomputer no longer can access our X-server. There are of course better ways to handle remote display, i.e better security, automatic transfer of the display environment etc. but this is beyond the scope of this book.

As you saw above, we introduced a new option --no-xshm, which tells Gimp not to try to use X shared memory. We have to do this because we ran Gimp on a different host. If we run Gimp at the same host that we displayed Gimp at, we can use X shared memory to speed things up a little bit, and also so we will be lean onsystem resources. There is another shared memory flag --no-shm which tells Gimp not to share memory with its plug-ins. It's generally good to let Gimp do this but if you encounter problems it can be wise to turn it off.

The --no-splash tells Gimp to not show the splash when it starts. If you just tell Gimp --no-splash-image then the splash will be shown, but without the image.

--verbose will start up Gimp+ a little more verbose and you will se in the shell how it's phrasing the different initiations files.

[olof@olof olof]$ gimp --verbose
parsing "/home/olof/.gimp/gtkrc"
parsing "/usr/local/share/gimp/gimprc"
parsing "/home/olof/.gimp/gimprc"
parsing "/home/olof/.gimp/pluginrc"

writing "/home/olof/.gimp/pluginrc"
parsing "/home/olof/.gimp/menurc"
Starting extensions: extension_script_fu

The last option is --no-data which you can use if you run Gimp in batch mode and don't need brushes, gradients, palettes or patterns. The start up time for Gimp will then be minimized.

Initiations files aka rc files

Gimp has a lot of initiations files which controls the behavior of Gimp. Most of the options that you set in different rc files are done by the preference dialog see chapter 5. We will only take a look at the options that you can't set from the dialog.

gimprc and ~/.gimp/gimprc

The system-wide gimprc and the personal gimprc located in your gimp directory ( i.e usually ~/.gimp/gimprc) control nearly all of Gimp's options. To change things in your personal gimprc file (~/.gimp/gimprc) you have to bring it up in an editor and edit the file.

[olof@olof olof]$ xemacs ~/.gimp/gimprc

There won't be much in it, because most of the options are written in the system-wide gimprc file (usually /usr/local/share/gimp/gimprc). If you want to change a system-wide setting, then copy it from the system-wide rc file, paste it into your personal rc and then change the setting of it. Since the system-wide rc file is phrased before the personal rc file, everything written in the personal file will override what's written in the system-wide file. It's a good idea to open the system-wide rc file to get a glimpse of what you can change. If you are a system administrator it's wise to change the system-wide rc file to fit your site's needs. We will take a look at the rc file.

As you can see, the file is more or less self-explaining, and we will only comment on things that you can't set in the preference dialog.

# This is the system-wide gimprc file. Any change made in this file
# will affect all users of this system, provided that they are not
# overriding the default values in their personal gimprc file.
#
# Lines that start with a '#' are comments.
# Blank lines are ignored.

# The variable gimp_dir is set to either the interned value
# .gimp or the environment variable GIMP_DIRECTORY. If

# the path in GIMP_DIRECTORY is relative, it is considered
# relative to your home directory.

(prefix "/usr/local")
(exec_prefix "${prefix}")
(gimp_data_dir "${prefix}/share/gimp")
(gimp_plugin_dir "${exec_prefix}/lib/gimp/0.99")

You shouldn't change these preferences, but if you feel you must, you can only do it in an editor

# Set the temporary storage directory...files will appear here
# during the course of running the gimp. Most files will disappear
# when the gimp exits, but some files are likely to remain,
# such as working palette files, so it is best if this directory
# not be one that is shared by other users or is cleared on machine
# reboot such as /tmp.
(temp-path "${gimp_dir}/tmp")

# Set the swap file location. The gimp uses a tile based memory
# allocation scheme. The swap file is used to quickly and easily
# swap files out to disk and back in. Be aware that the swap file
# can easily get very large if the gimp is used with large images.
# Also, things can get horribly slow if the swap file is created on 
# a directory that is mounted over NFS.  For these reasons, it may 
# be desirable to put your swap file in "/tmp".
(swap-path "${gimp_dir}")

# Set the brush search path...this path will be searched for valid
#  brushes at startup.
(brush-path "${gimp_dir}/brushes:${gimp_data_dir}/brushes")

# Specify a default brush. If none is specified it defaults to the

#  "1circle.gbr" brush which is just a single pixel sized brush.
#  The brush is searched for in the brush path.
(default-brush "19fcircle.gbr")