display-file - Render display into image file
display-file: [-flushcmd=<command>] [-flushframe=<n>]
Renders an image into a file. The file can be a framebuffer device
(e.g. /dev/fb0), in which case a reasonable representation of the image
will be drawn on the console so long as the program’s mode matches the
Note: This target generates no input. The display-multi(7)
target can be used in order to see (and control) what the
program does (using a normal target) and then generate a
snapshot when the program exits.
filename is the file to render the images to. If the filename is a PPM
file (has the extension .ppm), then the image will be generated at
ggiClose(3) time. Otherwise the file is a custom GGIFILE format and is
The display-file target can be used to generate movies from running
LibGGI applications. To do this, set -flushcmd to a shell command to
execute at the times given by one of the two other parameters. This
looks typically like:
ppmtogif foo.ppm > foo.%04d.gif
The command is passed through a printf(3) which has the current count
of saved frames as an argument (or rather as 10 arguments to allow a
few more complex commands).
This shell command is either executed at every n-th invocation of
ggiFlush or every t seconds, where t can have fractional components
(specified as decimal).
Note, that the invocation of the shell command will slow down the
program, so make sure you use a reasonable value, if you use the
The primary file is updated before every invocation of the shell
· DirectBuffer always available.