OK, Progress. I now have a working "fam2font" program which is short enough to post here: ---------------------fam2font.c------------------------------------------------ #include <stdio.h> #include <fontconfig/fontconfig.h> int main (int argc, char *argv[]) { FcPattern *pattern = 0, *match = 0; FcChar8 *file = 0; if ((argc < 2) || !(FcInit())) return -1; pattern = FcPatternBuild(0,FC_FAMILY,FcTypeString,argv[1],0); FcDefaultSubstitute(pattern); if (!(match = FcFontMatch(0,pattern,0))) return -1; if (FcPatternGetString(match,FC_FILE,0,&file) != FcResultMatch) return -1; fprintf(stdout,"%s\n",file); return 0; } ------------------------------------------------------------------------------------- Compile with: gcc -Wall fam2font.c -lfontconfig -o fam2font Example usage: gnome-font-viewer `./fam2font fixed` gnome-font-viewer `./fam2font Times` Those worked OK for me, but I was expecting to get a sans-serif font with: gnome-font-viewer `./fam2font Helvetica` instead I got the same serif font as "Times" What are the possible font family names? Why is "Helvetica" not matched to a sans-serif font? John Ellson