diff --git a/arch/arm/bits/alltypes.h.sh b/arch/arm/bits/alltypes.h.sh
index 748b8730..f1aca666 100755
--- a/arch/arm/bits/alltypes.h.sh
+++ b/arch/arm/bits/alltypes.h.sh
@@ -70,9 +70,9 @@ STRUCT timeval { time_t tv_sec; int tv_usec; };
 STRUCT timespec { time_t tv_sec; long tv_nsec; };
 
 TYPEDEF int pid_t;
-TYPEDEF int id_t;
-TYPEDEF int uid_t;
-TYPEDEF int gid_t;
+TYPEDEF unsigned id_t;
+TYPEDEF unsigned uid_t;
+TYPEDEF unsigned gid_t;
 TYPEDEF int key_t;
 
 TYPEDEF struct __pthread * pthread_t;
diff --git a/arch/i386/bits/alltypes.h.sh b/arch/i386/bits/alltypes.h.sh
index 85776a83..381e2c9b 100755
--- a/arch/i386/bits/alltypes.h.sh
+++ b/arch/i386/bits/alltypes.h.sh
@@ -84,9 +84,9 @@ STRUCT timeval { time_t tv_sec; int tv_usec; };
 STRUCT timespec { time_t tv_sec; long tv_nsec; };
 
 TYPEDEF int pid_t;
-TYPEDEF int id_t;
-TYPEDEF int uid_t;
-TYPEDEF int gid_t;
+TYPEDEF unsigned id_t;
+TYPEDEF unsigned uid_t;
+TYPEDEF unsigned gid_t;
 TYPEDEF int key_t;
 
 TYPEDEF struct __pthread * pthread_t;
diff --git a/arch/microblaze/bits/alltypes.h.sh b/arch/microblaze/bits/alltypes.h.sh
index a5acd494..032b45a4 100755
--- a/arch/microblaze/bits/alltypes.h.sh
+++ b/arch/microblaze/bits/alltypes.h.sh
@@ -70,9 +70,9 @@ STRUCT timeval { time_t tv_sec; int tv_usec; };
 STRUCT timespec { time_t tv_sec; long tv_nsec; };
 
 TYPEDEF int pid_t;
-TYPEDEF int id_t;
-TYPEDEF int uid_t;
-TYPEDEF int gid_t;
+TYPEDEF unsigned id_t;
+TYPEDEF unsigned uid_t;
+TYPEDEF unsigned gid_t;
 TYPEDEF int key_t;
 
 TYPEDEF struct __pthread * pthread_t;
diff --git a/arch/mips/bits/alltypes.h.sh b/arch/mips/bits/alltypes.h.sh
index a5acd494..032b45a4 100755
--- a/arch/mips/bits/alltypes.h.sh
+++ b/arch/mips/bits/alltypes.h.sh
@@ -70,9 +70,9 @@ STRUCT timeval { time_t tv_sec; int tv_usec; };
 STRUCT timespec { time_t tv_sec; long tv_nsec; };
 
 TYPEDEF int pid_t;
-TYPEDEF int id_t;
-TYPEDEF int uid_t;
-TYPEDEF int gid_t;
+TYPEDEF unsigned id_t;
+TYPEDEF unsigned uid_t;
+TYPEDEF unsigned gid_t;
 TYPEDEF int key_t;
 
 TYPEDEF struct __pthread * pthread_t;
diff --git a/arch/powerpc/bits/alltypes.h.sh b/arch/powerpc/bits/alltypes.h.sh
index 77d335bb..0cb90007 100755
--- a/arch/powerpc/bits/alltypes.h.sh
+++ b/arch/powerpc/bits/alltypes.h.sh
@@ -70,9 +70,9 @@ STRUCT timeval { time_t tv_sec; int tv_usec; };
 STRUCT timespec { time_t tv_sec; long tv_nsec; };
 
 TYPEDEF int pid_t;
-TYPEDEF int id_t;
-TYPEDEF int uid_t;
-TYPEDEF int gid_t;
+TYPEDEF unsigned id_t;
+TYPEDEF unsigned uid_t;
+TYPEDEF unsigned gid_t;
 TYPEDEF int key_t;
 
 TYPEDEF struct __pthread * pthread_t;
diff --git a/arch/x86_64/bits/alltypes.h.sh b/arch/x86_64/bits/alltypes.h.sh
index e5b8d47f..8f122c32 100755
--- a/arch/x86_64/bits/alltypes.h.sh
+++ b/arch/x86_64/bits/alltypes.h.sh
@@ -70,9 +70,9 @@ STRUCT timeval { time_t tv_sec; long tv_usec; };
 STRUCT timespec { time_t tv_sec; long tv_nsec; };
 
 TYPEDEF int pid_t;
-TYPEDEF int id_t;
-TYPEDEF unsigned int uid_t;
-TYPEDEF unsigned int gid_t;
+TYPEDEF unsigned id_t;
+TYPEDEF unsigned uid_t;
+TYPEDEF unsigned gid_t;
 TYPEDEF int key_t;
 
 TYPEDEF struct __pthread * pthread_t;
diff --git a/src/passwd/getgrent_a.c b/src/passwd/getgrent_a.c
index 780560dd..2cb85215 100644
--- a/src/passwd/getgrent_a.c
+++ b/src/passwd/getgrent_a.c
@@ -1,6 +1,13 @@
 #include "pwf.h"
 #include <pthread.h>
 
+static unsigned atou(char **s)
+{
+	unsigned x;
+	for (x=0; **s-'0'<10U; ++*s) x=10*x+(**s-'0');
+	return x;
+}
+
 struct group *__getgrent_a(FILE *f, struct group *gr, char **line, size_t *size, char ***mem, size_t *nmem)
 {
 	ssize_t l;
@@ -24,8 +31,8 @@ struct group *__getgrent_a(FILE *f, struct group *gr, char **line, size_t *size,
 		*s++ = 0; gr->gr_passwd = s;
 		if (!(s = strchr(s, ':'))) continue;
 
-		*s++ = 0; gr->gr_gid = atoi(s);
-		if (!(s = strchr(s, ':'))) continue;
+		*s++ = 0; gr->gr_gid = atou(&s);
+		if (*s != ':') continue;
 
 		*s++ = 0; mems = s;
 		break;
diff --git a/src/passwd/getpwent_a.c b/src/passwd/getpwent_a.c
index 1bd7f4fc..34842a07 100644
--- a/src/passwd/getpwent_a.c
+++ b/src/passwd/getpwent_a.c
@@ -1,6 +1,13 @@
 #include "pwf.h"
 #include <pthread.h>
 
+static unsigned atou(char **s)
+{
+	unsigned x;
+	for (x=0; **s-'0'<10U; ++*s) x=10*x+(**s-'0');
+	return x;
+}
+
 struct passwd *__getpwent_a(FILE *f, struct passwd *pw, char **line, size_t *size)
 {
 	ssize_t l;
@@ -23,11 +30,11 @@ struct passwd *__getpwent_a(FILE *f, struct passwd *pw, char **line, size_t *siz
 		*s++ = 0; pw->pw_passwd = s;
 		if (!(s = strchr(s, ':'))) continue;
 
-		*s++ = 0; pw->pw_uid = atoi(s);
-		if (!(s = strchr(s, ':'))) continue;
+		*s++ = 0; pw->pw_uid = atou(&s);
+		if (*s != ':') continue;
 
-		*s++ = 0; pw->pw_gid = atoi(s);
-		if (!(s = strchr(s, ':'))) continue;
+		*s++ = 0; pw->pw_gid = atou(&s);
+		if (*s != ':') continue;
 
 		*s++ = 0; pw->pw_gecos = s;
 		if (!(s = strchr(s, ':'))) continue;