Improve the error message when invalid formats are used for one-liners #7098
Description
Description of the problem
Note the typo -pnf below. It should be -png. Ideally GMT should report an error like:
"Unrecognized graphics format pnf".
$ gmt basemap -Rg -JH20c -Ba -pnf map
gmt [ERROR]: Shared GMT module not found: basemap
ERROR: No module named basemap was found. This could mean one of four cases:
1. There actually is no such module; please check your spelling.
2. You used a modern mode module name while running in GMT classic mode.
3. Module exists in the GMT supplemental library, but the library could not be found.
4. Module exists in a GMT custom library, but none was specified via GMT_CUSTOM_LIBS.
Shared libraries must be in standard system paths or set via environmental parameter LD_LIBRARY_PATH.
System information
- Operating system: Linux
- GMT version (
gmt --version): 6.5.0_111fa6d_2022.08.11