diff --git a/usr.bin/top/machine.c b/usr.bin/top/machine.c
index 66ecf5afb39f..fbea363da3c2 100644
--- a/usr.bin/top/machine.c
+++ b/usr.bin/top/machine.c
@@ -914,7 +914,7 @@ get_process_info(struct system_info *si, struct process_select *sel,
 static char fmt[512];	/* static area where result is built */
 
 char *
-format_next_process(caddr_t xhandle, char *(*get_userid)(int), int flags)
+format_next_process(caddr_t xhandle, char *(*get_userid)(uid_t), int flags)
 {
 	struct kinfo_proc *pp;
 	const struct kinfo_proc *oldp;
diff --git a/usr.bin/top/machine.h b/usr.bin/top/machine.h
index 0e8e2f2c6eb6..20d6e0faec16 100644
--- a/usr.bin/top/machine.h
+++ b/usr.bin/top/machine.h
@@ -75,7 +75,7 @@ struct process_select
 /* routines defined by the machine dependent module */
 
 char	*format_header(char *uname_field);
-char	*format_next_process(caddr_t handle, char *(*get_userid)(int),
+char	*format_next_process(caddr_t handle, char *(*get_userid)(uid_t),
 	    int flags);
 void	 toggle_pcpustats(void);
 void	 get_system_info(struct system_info *si);
diff --git a/usr.bin/top/screen.c b/usr.bin/top/screen.c
index a564a5cfb265..22cf7b93d32f 100644
--- a/usr.bin/top/screen.c
+++ b/usr.bin/top/screen.c
@@ -25,7 +25,6 @@
 #include <sys/ioctl.h>
 #include <stdlib.h>
 #include <string.h>
-#define TERMIOS
 #include <termios.h>
 #include <curses.h>
 #include <termcap.h>
diff --git a/usr.bin/top/top.c b/usr.bin/top/top.c
index e03178dd2801..d44dd9898810 100644
--- a/usr.bin/top/top.c
+++ b/usr.bin/top/top.c
@@ -206,7 +206,7 @@ main(int argc, char *argv[])
     int displays = 0;		/* indicates unspecified */
     int sel_ret = 0;
     time_t curr_time;
-    char *(*get_userid)(int) = username;
+    char *(*get_userid)(uid_t) = username;
     char *uname_field = "USERNAME";
     char *header_text;
     char *env_top;
diff --git a/usr.bin/top/username.c b/usr.bin/top/username.c
index 74eaf9b4fc32..c962751090ad 100644
--- a/usr.bin/top/username.c
+++ b/usr.bin/top/username.c
@@ -37,29 +37,27 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 
 #include "utils.h"
 #include "username.h"
 
 struct hash_el {
-    int  uid;
+    uid_t  uid;
     char name[MAXLOGNAME];
 };
 
 #define    is_empty_hash(x)	(hash_table[x].name[0] == 0)
 
 /* simple minded hashing function */
-/* Uid "nobody" is -2 results in hashit(-2) = -2 which is out of bounds for
-   the hash_table.  Applied abs() function to fix. 2/16/96 tpugh
-*/
-#define    hashit(i)	(abs(i) % Table_size)
+#define    hashit(i)	(i % Table_size)
 
 /* K&R requires that statically declared tables be initialized to zero. */
 /* We depend on that for hash_table and YOUR compiler had BETTER do it! */
 static struct hash_el hash_table[Table_size];
 
 
-char *username(int uid)
+char *username(uid_t uid)
 {
     int hashindex;
 
@@ -72,7 +70,7 @@ char *username(int uid)
     return(hash_table[hashindex].name);
 }
 
-int userid(char username[])
+uid_t userid(char username[])
 {
     struct passwd *pwd;
 
@@ -93,7 +91,7 @@ int userid(char username[])
 }
 
 /* wecare 1 = enter it always, 0 = nice to have */
-int enter_user(int uid, char name[], bool wecare)
+int enter_user(uid_t uid, char name[], bool wecare)
 {
     int hashindex;
 
@@ -124,7 +122,7 @@ int enter_user(int uid, char name[], bool wecare)
  */
 
 int
-get_user(int uid)
+get_user(uid_t uid)
 {
     struct passwd *pwd;
 
diff --git a/usr.bin/top/username.h b/usr.bin/top/username.h
index b06a227890fc..2975a9ee9480 100644
--- a/usr.bin/top/username.h
+++ b/usr.bin/top/username.h
@@ -12,12 +12,13 @@
 #define USERNAME_H
 
 #include <stdbool.h>
+#include <unistd.h>
 
-int	 enter_user(int uid, char *name, bool wecare);
-int	 get_user(int uid);
+int	 enter_user(uid_t uid, char *name, bool wecare);
+int	 get_user(uid_t uid);
 void	 init_hash(void);
-char 	*username(int uid);
-int 	 userid(char *username);
+char 	*username(uid_t uid);
+uid_t 	 userid(char *username);
 
 /*
  *  "Table_size" defines the size of the hash tables used to map uid to
diff --git a/usr.bin/top/utils.c b/usr.bin/top/utils.c
index 2f51da76e516..4a8a0d8817d4 100644
--- a/usr.bin/top/utils.c
+++ b/usr.bin/top/utils.c
@@ -59,7 +59,7 @@ atoiwi(char *str)
 				 */
 _Static_assert(sizeof(int) <= 4, "buffer too small for this sized int");
 
-char *itoa(int val)
+char *itoa(unsigned int val)
 {
     char *ptr;
     static char buffer[16];	/* result is built here */
@@ -87,7 +87,7 @@ char *itoa(int val)
  *	a front end to a more general routine for efficiency.
  */
 
-char *itoa7(int val)
+char *itoa7(unsigned int val)
 {
     char *ptr;
     static char buffer[16];	/* result is built here */
diff --git a/usr.bin/top/utils.h b/usr.bin/top/utils.h
index de993d0208e9..d04645dd8a17 100644
--- a/usr.bin/top/utils.h
+++ b/usr.bin/top/utils.h
@@ -11,8 +11,8 @@
  */
 
 int atoiwi(char *);
-char *itoa(int);
-char *itoa7(int);
+char *itoa(unsigned int);
+char *itoa7(unsigned int);
 int digits(int);
 char *strecpy(char *, char *);
 char **argparse(char *, int *);