no exit on errors

lib/fimg-file.c

@@ -117,7 +117,7 @@ if (NULL==(fp = fopen(fname, "r"))) {
 	}
 foo = fread(&filehead, sizeof(FimgFileHead), 1, fp);  
 if (1 != foo) {
-	fprintf(stderr, "%s : short read\n", fname);
+	fprintf(stderr, "%s: short read on '%s'\n", __func__, fname);
 	fclose(fp);
 	return -1;
 	}
@@ -127,15 +127,17 @@ if (	(filehead.w != where->width) ||
 	(filehead.h != where->height) ||
 	(filehead.t != where->type) ) {
 
-	fprintf(stderr, "file '%s' incompatible\n", fname);
-	exit(3);
+	fprintf(stderr, "%s: file '%s' incompatible\n", __func__, fname);
+	fclose(fp);
+	return -17;
 	}
 
 nbre = filehead.w*filehead.h*filehead.t;	/* ugly quirk */
 foo = fread(where->R, sizeof(float), nbre, fp);
 if (nbre != foo) {
-	fprintf(stderr, "err read '%s' : %d\n", fname, errno);
-	exit(3);
+	fprintf(stderr, "%s: err read '%s' : %d\n", __func__, fname, errno);
+	fclose(fp);
+	return -18;
 	}
 
 fclose(fp);