diff --git a/backend/raster.c b/backend/raster.c
index b26dcbaa..d6c61d72 100644
--- a/backend/raster.c
+++ b/backend/raster.c
@@ -96,7 +96,7 @@ int save_raster_image_to_file(struct zint_symbol *symbol, int image_height, int
     char *rotated_pixbuf;
     
     if (!(rotated_pixbuf = (char *) malloc(image_width * image_height))) {
-        printf("Insufficient memory for pixel buffer (F50)");
+        strcpy(symbol->errtxt, "Insufficient memory for pixel buffer (F50)");
         return ZINT_ERROR_ENCODING_PROBLEM;
     }
 
@@ -490,7 +490,7 @@ int plot_raster_maxicode(struct zint_symbol *symbol, int rotate_angle, int data_
     image_height = (300 + (2 * yoffset * 2)) * scaler;
 
     if (!(pixelbuf = (char *) malloc(image_width * image_height))) {
-        printf("Insufficient memory for pixel buffer (F55)");
+        strcpy(symbol->errtxt, "Insufficient memory for pixel buffer (F55)");
         return ZINT_ERROR_ENCODING_PROBLEM;
     } else {
         for (i = 0; i < (image_width * image_height); i++) {
@@ -501,7 +501,7 @@ int plot_raster_maxicode(struct zint_symbol *symbol, int rotate_angle, int data_
     hexagon_size = (int)scaler * 10;
     
     if (!(scaled_hexagon = (char *) malloc(hexagon_size * hexagon_size))) {
-        printf("Insufficient memory for pixel buffer (F56)");
+        strcpy(symbol->errtxt, "Insufficient memory for pixel buffer (F56)");
         free(scaled_hexagon);
         return ZINT_ERROR_ENCODING_PROBLEM;
     } else {
@@ -611,7 +611,7 @@ int plot_raster_dotty(struct zint_symbol *symbol, int rotate_angle, int data_typ
 
     /* Apply scale options by creating another pixel buffer */
     if (!(scaled_pixelbuf = (char *) malloc(scale_width * scale_height))) {
-        printf("Insufficient memory for pixel buffer (F57)");
+        strcpy(symbol->errtxt, "Insufficient memory for pixel buffer (F57)");
         return ZINT_ERROR_ENCODING_PROBLEM;
     } else {
         for (i = 0; i < (scale_width * scale_height); i++) {
@@ -786,7 +786,7 @@ int plot_raster_default(struct zint_symbol *symbol, int rotate_angle, int data_t
     image_height = 2 * (symbol->height + textoffset + yoffset + yoffset);
 
     if (!(pixelbuf = (char *) malloc(image_width * image_height))) {
-        printf("Insufficient memory for pixel buffer (F58)");
+        strcpy(symbol->errtxt, "Insufficient memory for pixel buffer (F58)");
         return ZINT_ERROR_ENCODING_PROBLEM;
     } else {
         for (i = 0; i < (image_width * image_height); i++) {
@@ -1089,7 +1089,7 @@ int plot_raster_default(struct zint_symbol *symbol, int rotate_angle, int data_t
     /* Apply scale options by creating another pixel buffer */
     if (!(scaled_pixelbuf = (char *) malloc(scale_width * scale_height))) {
         free(pixelbuf);
-        printf("Insufficient memory for pixel buffer (F59)");
+        strcpy(symbol->errtxt, "Insufficient memory for pixel buffer (F59)");
         return ZINT_ERROR_ENCODING_PROBLEM;
     } else {
         for (i = 0; i < (scale_width * scale_height); i++) {