When specifying an output format that does not exist (in this case due to a typo), pscoast
goes renegade (i.e. classic mode), and outputs postscript to stdout
. E.g.
$ gmt begin test PDf; gmt pscoast -W -JX10c -RNO; gmt end
Suggestion: If possible, gmt begin […] should check if the specified output format is valid. If not, stop the script. Not sure how this would be implemented.