[Gnuplot-info] pulling x-axis time information from a binary file

[jr <joh...@io...>]

Hello everybody,

I have a binary file that was created with pack("l*",$time,$value); from
php.

I can plot the contents of the file fine with

unset key
set xtics rotate
plot 'data.bin' binary format='%int32%int32' using 1:2 with lines

however, i would like to have the tics on the x-axis as readable
date/time.
but when i use this (with or without set timefmt "%s"): 

unset key
set xdata time
set format x "%r %D"
set xtics rotate
plot 'data.bin' binary format='%int32%int32' u 1:2 with lines

i only get an error:

gnuplot> plot 'data.bin' binary format='%int32%int32' u 1:2 with lines
                                                                 ^
         line 0: warning: Skipping data file with no valid points

gnuplot> plot 'data.bin' binary format='%int32%int32' u 1:2 with lines
                                                                      ^
         line 0: x range is invalid

what am i doing wrong or how can i read time values from a binary file?

Thanks,
Johannes