diff --git a/backend_canonselphy.c b/backend_canonselphy.c
index 3573edb..6d06b3d 100644
--- a/backend_canonselphy.c
+++ b/backend_canonselphy.c
@@ -27,16 +27,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND canonselphy_backend
 
 #include "backend_common.h"
diff --git a/backend_canonselphyneo.c b/backend_canonselphyneo.c
index 4b0f7de..24f810a 100644
--- a/backend_canonselphyneo.c
+++ b/backend_canonselphyneo.c
@@ -27,16 +27,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND canonselphyneo_backend
 
 #include "backend_common.h"
diff --git a/backend_common.c b/backend_common.c
index 00921e4..22ab12e 100644
--- a/backend_common.c
+++ b/backend_common.c
@@ -29,6 +29,7 @@
 
 #include "backend_common.h"
 #include <errno.h>
+#include <signal.h>
 
 #define BACKEND_VERSION "0.96"
 #ifndef URI_PREFIX
diff --git a/backend_common.h b/backend_common.h
index af783ee..667de17 100644
--- a/backend_common.h
+++ b/backend_common.h
@@ -35,7 +35,6 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
-#include <signal.h>
 
 #include <libusb.h>
 #include <arpa/inet.h>
diff --git a/backend_dnpds40.c b/backend_dnpds40.c
index 4b4b287..157d89e 100644
--- a/backend_dnpds40.c
+++ b/backend_dnpds40.c
@@ -41,16 +41,6 @@
    assume the worst */
 //#define STATE_DIR "/tmp"
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND dnpds40_backend
 
 #include "backend_common.h"
diff --git a/backend_hiti.c b/backend_hiti.c
index e4ddf05..62ced37 100644
--- a/backend_hiti.c
+++ b/backend_hiti.c
@@ -27,16 +27,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND hiti_backend
 
 #include "backend_common.h"
diff --git a/backend_kodak1400.c b/backend_kodak1400.c
index a2f9e13..662c2c3 100644
--- a/backend_kodak1400.c
+++ b/backend_kodak1400.c
@@ -27,16 +27,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND kodak1400_backend
 
 #include "backend_common.h"
diff --git a/backend_kodak605.c b/backend_kodak605.c
index 5a3e194..ad0daa7 100644
--- a/backend_kodak605.c
+++ b/backend_kodak605.c
@@ -27,16 +27,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND kodak605_backend
 
 #include "backend_common.h"
diff --git a/backend_kodak6800.c b/backend_kodak6800.c
index c2daa54..8895891 100644
--- a/backend_kodak6800.c
+++ b/backend_kodak6800.c
@@ -31,16 +31,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND kodak6800_backend
 
 #include "backend_common.h"
diff --git a/backend_magicard.c b/backend_magicard.c
index adafd52..157a69f 100644
--- a/backend_magicard.c
+++ b/backend_magicard.c
@@ -27,22 +27,12 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <time.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <string.h>
-
 #define BACKEND magicard_backend
 
 #include "backend_common.h"
 
+#include <time.h>
+
 /* Exported */
 #define USB_VID_MAGICARD     0x0C1F
 #define USB_PID_MAGICARD_TANGO2E 0x1800
diff --git a/backend_mitsu70x.c b/backend_mitsu70x.c
index f738dcf..c58cc49 100644
--- a/backend_mitsu70x.c
+++ b/backend_mitsu70x.c
@@ -27,15 +27,9 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
+#define BACKEND mitsu70x_backend
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
+#include "backend_common.h"
 
 /* For Integration into gutenprint */
 #if defined(HAVE_CONFIG_H)
@@ -65,10 +59,6 @@
 #warning "No dynamic loading support!"
 #endif
 
-#define BACKEND mitsu70x_backend
-
-#include "backend_common.h"
-
 // #include "lib70x/libMitsuD70ImageReProcess.h"
 
 #ifndef LUT_LEN
diff --git a/backend_mitsu9550.c b/backend_mitsu9550.c
index 529de70..7f652d1 100644
--- a/backend_mitsu9550.c
+++ b/backend_mitsu9550.c
@@ -27,24 +27,15 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
+#define BACKEND mitsu9550_backend
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
+#include "backend_common.h"
 
 /* For Integration into gutenprint */
 #if defined(HAVE_CONFIG_H)
 #include <config.h>
 #endif
 
-#define BACKEND mitsu9550_backend
-
-
 #if defined(USE_DLOPEN)
 #define WITH_DYNAMIC
 #include <dlfcn.h>
@@ -68,8 +59,6 @@
 #warning "No dynamic loading support!"
 #endif
 
-#include "backend_common.h"
-
 // #include "lib70x/libMitsuD70ImageReProcess.h"
 
 #ifndef LUT_LEN
diff --git a/backend_mitsud90.c b/backend_mitsud90.c
index 96c0827..2e8f762 100644
--- a/backend_mitsud90.c
+++ b/backend_mitsud90.c
@@ -27,16 +27,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND mitsud90_backend
 
 #include "backend_common.h"
diff --git a/backend_mitsup95d.c b/backend_mitsup95d.c
index 88b0406..e0586b3 100644
--- a/backend_mitsup95d.c
+++ b/backend_mitsup95d.c
@@ -31,16 +31,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND mitsup95d_backend
 
 #include "backend_common.h"
diff --git a/backend_shinkos1245.c b/backend_shinkos1245.c
index 2360a40..5103549 100644
--- a/backend_shinkos1245.c
+++ b/backend_shinkos1245.c
@@ -29,16 +29,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND shinkos1245_backend
 
 #include "backend_common.h"
diff --git a/backend_shinkos2145.c b/backend_shinkos2145.c
index 7a6394c..3839b91 100644
--- a/backend_shinkos2145.c
+++ b/backend_shinkos2145.c
@@ -31,16 +31,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND shinkos2145_backend
 
 #include "backend_common.h"
diff --git a/backend_shinkos6145.c b/backend_shinkos6145.c
index fb60690..17b2e11 100644
--- a/backend_shinkos6145.c
+++ b/backend_shinkos6145.c
@@ -37,16 +37,12 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
 
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
+#define BACKEND shinkos6145_backend
+
+#include "backend_common.h"
+#include "backend_sinfonia.h"
+
 #include <time.h>
 
 /* For Integration into gutenprint */
@@ -77,11 +73,6 @@
 #warning "No dynamic loading support!"
 #endif
 
-#define BACKEND shinkos6145_backend
-
-#include "backend_common.h"
-#include "backend_sinfonia.h"
-
 /* Image processing library function prototypes */
 typedef int (*ImageProcessingFN)(unsigned char *, unsigned short *, void *);
 typedef int (*ImageAvrCalcFN)(unsigned char *, unsigned short, unsigned short, unsigned char *);
@@ -812,7 +803,7 @@ static int shinkos6145_get_imagecorr(struct shinkos6145_ctx *ctx)
 	ctx->corrdata = malloc(sizeof(struct shinkos6145_correctionparam));
 	if (!ctx->corrdata) {
 		ERROR("Memory allocation failure\n");
-		ret = -ENOMEM;
+		ret = CUPS_BACKEND_FAILED;
 		goto done;
 	}
 	memset(ctx->corrdata, 0, sizeof(struct shinkos6145_correctionparam));
@@ -865,7 +856,7 @@ static int shinkos6145_get_eeprom(struct shinkos6145_ctx *ctx)
 	ctx->eeprom = malloc(ctx->eepromlen);
 	if (!ctx->eeprom) {
 		ERROR("Memory allocation failure\n");
-		ret = -ENOMEM;
+		ret = CUPS_BACKEND_FAILED;
 		goto done;
 	}
 	memcpy(ctx->eeprom, resp.data, ctx->eepromlen);
diff --git a/backend_shinkos6245.c b/backend_shinkos6245.c
index ee419d6..f8f86de 100644
--- a/backend_shinkos6245.c
+++ b/backend_shinkos6245.c
@@ -29,22 +29,13 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <time.h>
-
 #define BACKEND shinkos6245_backend
 
 #include "backend_common.h"
 #include "backend_sinfonia.h"
 
+#include <time.h>
+
 enum {
 	S_IDLE = 0,
 	S_PRINTER_READY_CMD,
diff --git a/backend_sinfonia.c b/backend_sinfonia.c
index e674a8d..7a1348b 100644
--- a/backend_sinfonia.c
+++ b/backend_sinfonia.c
@@ -27,16 +27,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #include "backend_common.h"
 #include "backend_sinfonia.h"
 
diff --git a/backend_sonyupd.c b/backend_sonyupd.c
index 5c9bb52..1c4bf12 100644
--- a/backend_sonyupd.c
+++ b/backend_sonyupd.c
@@ -27,16 +27,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND sonyupd_backend
 
 #include "backend_common.h"
diff --git a/backend_sonyupdneo.c b/backend_sonyupdneo.c
index 4a9a744..bdb5055 100644
--- a/backend_sonyupdneo.c
+++ b/backend_sonyupdneo.c
@@ -27,16 +27,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
 #define BACKEND sonyupdneo_backend
 
 #include "backend_common.h"