gdalmanage --version (return code: 0)
GDAL 2.2.1, released 2017/06/23
gdalmanage --help (return code: 1)
Usage: gdalmanage identify [-r] [-u] files*
or gdalmanage copy [-f driver] oldname newname
or gdalmanage rename [-f driver] oldname newname
or gdalmanage delete [-f driver] datasetname