diff --git a/elks/arch/i86/boot/setup.S b/elks/arch/i86/boot/setup.S
index ca86a563c..f79bbc1cb 100644
--- a/elks/arch/i86/boot/setup.S
+++ b/elks/arch/i86/boot/setup.S
@@ -79,6 +79,7 @@
 */
 
 #include <linuxmt/config.h>
+#include <linuxmt/devnum.h>
 #include <linuxmt/boot.h>
 
 // Relocating loader debug option
@@ -241,9 +242,9 @@ start_os:
 // Check for correct a.out header
 
 #ifdef CONFIG_ROMFS_FS
-	movw $0x0600,root_dev	// ROMFS is device 6,0
+	movw $DEV_ROM,root_dev	// ROMFS
 #else
-	movw $0x0380,root_dev	// floppy is device 3,128
+	movw $DEV_FD0,root_dev	// floppy 0
 #endif
 	mov $CONFIG_ROM_KERNEL_CODE,%ax	// DS = ROM a.out image
    	mov %ax,%ds
diff --git a/elks/fs/msdos/inode.c b/elks/fs/msdos/inode.c
index acd641424..ff10affcd 100644
--- a/elks/fs/msdos/inode.c
+++ b/elks/fs/msdos/inode.c
@@ -12,55 +12,56 @@
 #include <linuxmt/errno.h>
 #include <linuxmt/string.h>
 #include <linuxmt/stat.h>
+#include <linuxmt/devnum.h>
 #include <linuxmt/debug.h>
 
 #ifdef CONFIG_FS_DEV
 /* FAT device table, increase DEVDIR_SIZE and DEVINO_BASE to add entries*/
 struct msdos_devdir_entry devnods[DEVDIR_SIZE] = {
-    { "hda",	S_IFBLK | 0644, MKDEV(3, 0) },
-    { "hda1",	S_IFBLK | 0644, MKDEV(3, 1) },
-    { "hda2",	S_IFBLK | 0644, MKDEV(3, 2) },
-    { "hda3",	S_IFBLK | 0644, MKDEV(3, 3) },
-    { "hda4",	S_IFBLK | 0644, MKDEV(3, 4) },
-    { "hdb",	S_IFBLK | 0644, MKDEV(3, 32)},
-    { "hdb1",	S_IFBLK | 0644, MKDEV(3, 33)},
-    { "hdb2",	S_IFBLK | 0644, MKDEV(3, 34)},
-    { "hdb3",	S_IFBLK | 0644, MKDEV(3, 35)},
-    { "hdb4",	S_IFBLK | 0644, MKDEV(3, 36)},
-    { "hdc",	S_IFBLK | 0644, MKDEV(3, 64)},
-    { "hdc1",	S_IFBLK | 0644, MKDEV(3, 65)},
-    { "hdc2",	S_IFBLK | 0644, MKDEV(3, 66)},
-    { "hdc3",	S_IFBLK | 0644, MKDEV(3, 67)},
-    { "hdb4",	S_IFBLK | 0644, MKDEV(3, 68)},
-    { "hdd",	S_IFBLK | 0644, MKDEV(3, 96)},
-    { "hdd1",	S_IFBLK | 0644, MKDEV(3, 97)},
-    { "hdd2",	S_IFBLK | 0644, MKDEV(3, 98)},
-    { "hdd3",	S_IFBLK | 0644, MKDEV(3, 99)},
-    { "hdd4",	S_IFBLK | 0644, MKDEV(3,100)},
-    { "fd0",	S_IFBLK | 0644, MKDEV(3,128)},
-    { "fd1",	S_IFBLK | 0644, MKDEV(3,160)},
-    { "fd2",    S_IFBLK | 0644, MKDEV(3,192)},
-    { "fd3",    S_IFBLK | 0644, MKDEV(3,224)},
-    { "rd0",	S_IFBLK | 0644, MKDEV(1, 0) },
-    { "ssd",	S_IFBLK | 0644, MKDEV(2, 0) },
-    { "kmem",	S_IFCHR | 0644, MKDEV(1, 2) },
-    { "null",	S_IFCHR | 0644, MKDEV(1, 3) },
-    { "zero",	S_IFCHR | 0644, MKDEV(1, 5) },
-    { "tty1",	S_IFCHR | 0644, MKDEV(4, 0) },
-    { "tty2",	S_IFCHR | 0644, MKDEV(4, 1) },
-    { "tty3",	S_IFCHR | 0644, MKDEV(4, 2) },
-    { "ttyS0",	S_IFCHR | 0644, MKDEV(4, 64)},
-    { "ttyS1",	S_IFCHR | 0644, MKDEV(4, 65)},
-    { "console",S_IFCHR | 0600, MKDEV(4, 254)},
-    { "tty",	S_IFCHR | 0666, MKDEV(4, 255)},
-    { "ttyp0",	S_IFCHR | 0644, MKDEV(4, 8) },
-    { "ptyp0",	S_IFCHR | 0644, MKDEV(2, 8) },
-    { "ttyp1",	S_IFCHR | 0644, MKDEV(4, 9) },
-    { "ptyp1",	S_IFCHR | 0644, MKDEV(2, 9) },
-    { "tcpdev",	S_IFCHR | 0644, MKDEV(8, 0) },
-    { "ne0",	S_IFCHR | 0644, MKDEV(9, 0) },
-    { "wd0",	S_IFCHR | 0644, MKDEV(9, 1) },
-    { "3c0",	S_IFCHR | 0644, MKDEV(9, 2) },
+    { "hda",	S_IFBLK | 0644, DEV_HDA                     },
+    { "hda1",	S_IFBLK | 0644, DEV_HDA+1                   },
+    { "hda2",	S_IFBLK | 0644, DEV_HDA+2                   },
+    { "hda3",	S_IFBLK | 0644, DEV_HDA+3                   },
+    { "hda4",	S_IFBLK | 0644, DEV_HDA+4                   },
+    { "hdb",	S_IFBLK | 0644, DEV_HDB                     },
+    { "hdb1",	S_IFBLK | 0644, DEV_HDB+1                   },
+    { "hdb2",	S_IFBLK | 0644, DEV_HDB+2                   },
+    { "hdb3",	S_IFBLK | 0644, DEV_HDB+3                   },
+    { "hdb4",	S_IFBLK | 0644, DEV_HDB+4                   },
+    { "hdc",	S_IFBLK | 0644, DEV_HDC                     },
+    { "hdc1",	S_IFBLK | 0644, DEV_HDC+1                   },
+    { "hdc2",	S_IFBLK | 0644, DEV_HDC+2                   },
+    { "hdc3",	S_IFBLK | 0644, DEV_HDC+3                   },
+    { "hdc4",	S_IFBLK | 0644, DEV_HDC+4                   },
+    { "hdd",	S_IFBLK | 0644, DEV_HDD                     },
+    { "hdd1",	S_IFBLK | 0644, DEV_HDD+1                   },
+    { "hdd2",	S_IFBLK | 0644, DEV_HDD+2                   },
+    { "hdd3",	S_IFBLK | 0644, DEV_HDD+3                   },
+    { "hdd4",	S_IFBLK | 0644, DEV_HDD+4                   },
+    { "fd0",	S_IFBLK | 0644, DEV_FD0                     },
+    { "fd1",	S_IFBLK | 0644, DEV_FD1                     },
+    { "fd2",    S_IFBLK | 0644, DEV_FD2                     },
+    { "fd3",    S_IFBLK | 0644, DEV_FD3                     },
+    { "rd0",	S_IFBLK | 0644, MKDEV(RAM_MAJOR, 0)         },
+    { "ssd",	S_IFBLK | 0644, MKDEV(SSD_MAJOR, 0)         },
+    { "kmem",	S_IFCHR | 0644, MKDEV(MEM_MAJOR, 2)         },
+    { "null",	S_IFCHR | 0644, MKDEV(MEM_MAJOR, 3)         },
+    { "zero",	S_IFCHR | 0644, MKDEV(MEM_MAJOR, 5)         },
+    { "tty1",	S_IFCHR | 0644, MKDEV(TTY_MAJOR, 0)         },
+    { "tty2",	S_IFCHR | 0644, MKDEV(TTY_MAJOR, 1)         },
+    { "tty3",	S_IFCHR | 0644, MKDEV(TTY_MAJOR, 2)         },
+    { "ttyS0",	S_IFCHR | 0644, MKDEV(TTY_MAJOR, 64)        },
+    { "ttyS1",	S_IFCHR | 0644, MKDEV(TTY_MAJOR, 65)        },
+    { "console",S_IFCHR | 0600, MKDEV(TTY_MAJOR, 254)       },
+    { "tty",	S_IFCHR | 0666, MKDEV(TTY_MAJOR, 255)       },
+    { "ttyp0",	S_IFCHR | 0644, MKDEV(TTY_MAJOR, 8)         },
+    { "ttyp1",	S_IFCHR | 0644, MKDEV(TTY_MAJOR, 9)         },
+    { "ptyp0",	S_IFCHR | 0644, MKDEV(PTY_MASTER_MAJOR, 8)  },
+    { "ptyp1",	S_IFCHR | 0644, MKDEV(PTY_MASTER_MAJOR, 9)  },
+    { "tcpdev",	S_IFCHR | 0644, MKDEV(TCPDEV_MAJOR, 0)      },
+    { "ne0",	S_IFCHR | 0644, MKDEV(ETH_MAJOR, 0)         },
+    { "wd0",	S_IFCHR | 0644, MKDEV(ETH_MAJOR, 1)         },
+    { "3c0",	S_IFCHR | 0644, MKDEV(ETH_MAJOR, 2)         },
 };
 #endif
 
diff --git a/elks/fs/super.c b/elks/fs/super.c
index 896e9a403..352dfac2a 100644
--- a/elks/fs/super.c
+++ b/elks/fs/super.c
@@ -15,6 +15,7 @@
 #include <linuxmt/mm.h>
 #include <linuxmt/fs.h>
 #include <linuxmt/kdev_t.h>
+#include <linuxmt/devnum.h>
 #include <linuxmt/debug.h>
 
 #include <arch/system.h>
@@ -491,7 +492,7 @@ void mount_root(void)
     } while (*(++fs_type) && !retval);
 
 #ifdef CONFIG_BLK_DEV_BIOS
-    if (ROOT_DEV == 0x0380) {
+    if (ROOT_DEV == DEV_FD0) {
         if (!filp->f_op->release)
             printk("Release not defined\n");
         close_filp(d_inode, filp);
diff --git a/elks/include/linuxmt/devnum.h b/elks/include/linuxmt/devnum.h
new file mode 100644
index 000000000..e4fa07f04
--- /dev/null
+++ b/elks/include/linuxmt/devnum.h
@@ -0,0 +1,32 @@
+#ifndef __LINUXMT_DEVNUM_H
+#define __LINUXMT_DEVNUM_H
+
+#include <linuxmt/major.h>
+#include <linuxmt/kdev_t.h>
+
+/*
+ * Device numbers for block and character devices
+ *
+ * NOTE: If a block device MINOR_SHIFT changes, must be updated here also.
+ */
+
+/* block devices */
+#define DEV_HDA     MKDEV(BIOSHD_MAJOR, 0)
+#define DEV_HDB     MKDEV(BIOSHD_MAJOR, 32)
+#define DEV_HDC     MKDEV(BIOSHD_MAJOR, 64)
+#define DEV_HDD     MKDEV(BIOSHD_MAJOR, 96)
+#define DEV_FD0     MKDEV(BIOSHD_MAJOR, 128)
+#define DEV_FD1     MKDEV(BIOSHD_MAJOR, 160)
+#define DEV_FD2     MKDEV(BIOSHD_MAJOR, 192)
+#define DEV_FD3     MKDEV(BIOSHD_MAJOR, 224)
+#define DEV_ROM     MKDEV(ROMFLASH_MAJOR, 0)
+
+/* char devices */
+#define DEV_TTY1    MKDEV(TTY_MAJOR, 0)
+#define DEV_TTY2    MKDEV(TTY_MAJOR, 1)
+#define DEV_TTY3    MKDEV(TTY_MAJOR, 2)
+#define DEV_TTYS0   MKDEV(TTY_MAJOR, 64)
+#define DEV_TTYS1   MKDEV(TTY_MAJOR, 65)
+
+
+#endif /* !__LINUXMT_DEVNUM_H */
diff --git a/elks/include/linuxmt/dirent.h b/elks/include/linuxmt/dirent.h
index 5e9f7cf74..a115c36a4 100644
--- a/elks/include/linuxmt/dirent.h
+++ b/elks/include/linuxmt/dirent.h
@@ -2,8 +2,7 @@
 #define __LINUXMT_DIRENT_H
 
 #include <linuxmt/types.h>
-
-#define MAXNAMLEN       26      /* 14 for MINIX, 26 for FAT */
+#include <linuxmt/limits.h>
 
 struct dirent {
     u_ino_t         d_ino;
diff --git a/elks/include/linuxmt/fs.h b/elks/include/linuxmt/fs.h
index aab6f44a4..a8c379c97 100644
--- a/elks/include/linuxmt/fs.h
+++ b/elks/include/linuxmt/fs.h
@@ -40,13 +40,6 @@
 
 #endif /* __KERNEL__ */
 
-/*
- *  Now the file code is no longer dependent on bitmaps in unsigned
- *  longs, but uses the new fd_set structure..
- */
-
-#define NR_OPEN         20
-
 #define BLOCK_SIZE      1024
 #define BLOCK_SIZE_BITS 10
 
diff --git a/elks/include/linuxmt/kdev_t.h b/elks/include/linuxmt/kdev_t.h
index 183c5a0b2..07b46a8a2 100644
--- a/elks/include/linuxmt/kdev_t.h
+++ b/elks/include/linuxmt/kdev_t.h
@@ -4,14 +4,20 @@
 /* Some programs want their definitions of MAJOR and MINOR and MKDEV
  * from the kernel sources. Here we use unsigned short instead of __u16.
  */
+#ifdef __ASSEMBLER__
+#define _CAST_U16
+#else
+#define _CAST_U16   (unsigned short)
+#endif
+
 #define MINORBITS           8
 #define MINORMASK           ((1 << MINORBITS) - 1)
-#define MAJOR(dev)          ((unsigned short) ((dev) >> MINORBITS))
-#define MINOR(dev)          ((unsigned short) ((dev) & MINORMASK))
-#define MKDEV(major,minor)  ((unsigned short) (((major) << MINORBITS) | (minor)))
+#define MAJOR(dev)          (_CAST_U16 ((dev) >> MINORBITS))
+#define MINOR(dev)          (_CAST_U16 ((dev) & MINORMASK))
+#define MKDEV(major,minor)  (_CAST_U16 (((major) << MINORBITS) | (minor)))
 #define NODEV               MKDEV(0,0)
 
-#ifdef __KERNEL__
+#if defined(__KERNEL__) && !defined(__ASSEMBLER__)
 #include <arch/types.h>
 
 typedef __u16               kdev_t;
diff --git a/elks/include/linuxmt/limits.h b/elks/include/linuxmt/limits.h
index e9e0aa6b2..f5b95ae67 100644
--- a/elks/include/linuxmt/limits.h
+++ b/elks/include/linuxmt/limits.h
@@ -12,7 +12,7 @@
 #ifdef CONFIG_ASYNCIO
 #define KSTACK_BYTES    700     /* Size of kernel stacks w/async I/O */
 #else
-#define KSTACK_BYTES    640     /* Size of kernel stacks w/sync I/O */
+#define KSTACK_BYTES    640     /* Size of kernel stacks w/o async I/O */
 #endif
 #endif
 
@@ -34,10 +34,13 @@
 /* filesystem */
 #define NR_INODE        96      /* this should be bigger than NR_FILE */
 #define NR_FILE         64      /* this can well be larger on a larger system */
-#define NR_SUPER        6       /* max mounts */
+#define NR_OPEN         20      /* Max open files per process */
+#define NR_SUPER        6       /* Max mounts */
 
 #define PIPE_BUFSIZ     80      /* doesn't have to be power of two */
 
+#define MAXNAMLEN       26      /* Max filename, 14 for MINIX, 26 for FAT (not tunable) */
+
 #define NR_ALARMS       5       /* Max number of simultaneous alarms system-wide */
 
 #define MAX_PACKET_ETH 1536     /* Max packet size, 6 blocks of 256 bytes */
diff --git a/elks/init/main.c b/elks/init/main.c
index 274027377..8fbda79af 100644
--- a/elks/init/main.c
+++ b/elks/init/main.c
@@ -12,6 +12,7 @@
 #include <linuxmt/utsname.h>
 #include <linuxmt/netstat.h>
 #include <linuxmt/trace.h>
+#include <linuxmt/devnum.h>
 #include <arch/system.h>
 #include <arch/segment.h>
 #include <arch/ports.h>
@@ -252,17 +253,18 @@ static struct dev_name_struct {
 	const char *name;
 	int num;
 } devices[] = {
-	/* root_dev_name needs first 5 in order*/
-	{ "hda",     0x0300 },
-	{ "hdb",     0x0320 },
-	{ "hdc",     0x0340 },
-	{ "hdd",     0x0360 },
-	{ "fd0",     0x0380 },
-	{ "fd1",     0x03a0 },
-	{ "ttyS",    0x0440 },
-	{ "tty1",    0x0400 },
-	{ "tty2",    0x0401 },
-	{ "tty3",    0x0402 },
+	/* the 4 partitionable drives must be first */
+	{ "hda",     DEV_HDA },
+	{ "hdb",     DEV_HDB },
+	{ "hdc",     DEV_HDC },
+	{ "hdd",     DEV_HDD },
+	{ "fd0",     DEV_FD0 },
+	{ "fd1",     DEV_FD1 },
+	{ "ttyS0",   DEV_TTYS0 },
+	{ "ttyS1",   DEV_TTYS1 },
+	{ "tty1",    DEV_TTY1 },
+	{ "tty2",    DEV_TTY2 },
+	{ "tty3",    DEV_TTY3 },
 	{ NULL,           0 }
 };
 
@@ -282,7 +284,7 @@ static char * INITPROC root_dev_name(int dev)
 			if (i < 4) {
 				if (dev & 0x07) {
 					name[NAMEOFF+3] = '0' + (dev & 7);
-					name[NAMEOFF+4] = 0;
+					name[NAMEOFF+4] = '\0';
 				}
 			}
 			return name;
diff --git a/elkscmd/disk_utils/df.c b/elkscmd/disk_utils/df.c
index de0847b9b..15ae52eab 100644
--- a/elkscmd/disk_utils/df.c
+++ b/elkscmd/disk_utils/df.c
@@ -37,8 +37,7 @@ struct dnames {
 	char *name;
 	char *mpoint;
 };
-struct dnames *devname(char *);
-static char *dev_name(dev_t);
+struct dnames *device_path(char *);
 int df_fat(char *, int);
 
 int iflag= 0;	/* Focus on inodes instead of blocks. */
@@ -85,7 +84,7 @@ int main(int argc, char *argv[])
   if (argc > 1)
 	device = argv[1];
 
-  dname = devname(device);
+  dname = device_path(device);
   if (!(blockdev = dname->name)) {
 	fprintf(stderr, "Can't find /dev/ device for %s\n", device);
 	exit(1);
@@ -105,7 +104,7 @@ int main(int argc, char *argv[])
 	int i;
   	for (i = 0; i < NR_SUPER; i++) {
 		if (ustatfs(i, &statfs, UF_NOFREESPACE) >= 0) {
-			char *nm = dev_name(statfs.f_dev);
+			char *nm = devname(statfs.f_dev, S_IFBLK);
 			char *filler = "  ";		/* Text alignment */
 			if (Pflag) filler = "";
 			if (statfs.f_type > FST_MSDOS || (statfs.f_type == FST_MSDOS && (Pflag||iflag))) 
@@ -277,7 +276,7 @@ bit_t bit_count(unsigned blocks, bit_t bits, int fd)
  */
 
 /* return /dev/ device from dirname */
-struct dnames *devname(char *dirname)
+struct dnames *device_path(char *dirname)
 {
    static char dev[] = "/dev";
    struct stat st, dst;
@@ -322,44 +321,3 @@ struct dnames *devname(char *dirname)
    closedir(fp);
    return NULL;
 }
-
-/*
- * Convert a block device number to name.
- * From mount.c
- */
-static struct dev_name_struct {
-        char *name;
-        dev_t num;
-} devices[] = {
-        /* root_dev_name needs first 5 in order*/
-        { "hda",     0x0300 },
-        { "hdb",     0x0320 },
-        { "hdc",     0x0340 },
-        { "hdd",     0x0360 },
-        { "fd0",     0x0380 },
-        { "fd1",     0x03a0 },
-        { "ssd",     0x0200 },
-        { "rd",      0x0100 },
-        { NULL,           0 }
-};
-
-static char *dev_name(dev_t dev)
-{
-	int i;
-#define NAMEOFF 5
-	static char name[10] = "/dev/";
-
-	for (i=0; i<sizeof(devices)/sizeof(devices[0])-1; i++) {
-		if (devices[i].num == (dev & 0xfff0)) {
-			strcpy(&name[NAMEOFF], devices[i].name);
-			if (i < 4) {
-				if (dev & 0x07) {
-					name[NAMEOFF+3] = '0' + (dev & 7);
-					name[NAMEOFF+4] = 0;
-				}
-			}
-			return name;
-		}
-	}
-	return NULL;
-}
diff --git a/elkscmd/screen/screen.c b/elkscmd/screen/screen.c
index efcb9a7fd..fd3665cfc 100644
--- a/elkscmd/screen/screen.c
+++ b/elkscmd/screen/screen.c
@@ -81,8 +81,8 @@ extern char AnsiVersion[];
 extern flowctl;
 extern errno;
 extern sys_nerr;
-extern char *getenv(), *MakeTermcap();
-extern char *getlogin(), *ttyname();
+extern char *MakeTermcap();
+extern char *getlogin();
 static AttacherFinit(), Finit(), SigHup(), SigChld();
 static char *MakeBellMsg(), *Filename(), **SaveArgs(), *GetTtyName();
 
diff --git a/elkscmd/sys_utils/makeboot.c b/elkscmd/sys_utils/makeboot.c
index 924371d0b..2ac79f840 100644
--- a/elkscmd/sys_utils/makeboot.c
+++ b/elkscmd/sys_utils/makeboot.c
@@ -77,39 +77,6 @@ char bootblock[1024];				/* 1024 for MINIX, 512 for FAT */
 char *rootdevice;
 char *fsname[3] = { "Unknown", "Minix", "FAT" };
 
-/* return /dev name of device*/
-char *devname(dev_t dev)
-{
-	DIR *dp;
-	struct dirent *d;
-	struct stat st;
-	static char devdir[] = "/dev";
-	static char name[16];
-
-	dp = opendir(devdir);
-	if (dp == 0) {
-		perror(devdir);
-		return NULL;
-	}
-	strcpy(name, devdir);
-	strcat(name, "/");
-
-	while ((d = readdir(dp)) != NULL) {
-		if (d->d_name[0] == '.')
- 			continue;
-		strcpy(name + sizeof(devdir), d->d_name);
-		if (stat(name, &st) == 0) {
-			if (S_ISBLK(st.st_mode) && st.st_rdev == dev) {
-				closedir(dp);
-				return name;
-			}
-		}
-	}
-	closedir(dp);
-	fprintf(stderr, "Can't find device: 0x%x\n", dev);
-	return NULL;
-}
-
 /* determine and return filesystem type*/
 int get_fstype(int fd)
 {
@@ -398,7 +365,9 @@ int main(int ac, char **av)
 	}
 
 	rootdev = sbuf.st_dev;
-	rootdevice = devname(rootdev);
+	rootdevice = devname(rootdev, S_IFBLK);
+    if (!rootdevice)
+	    fatalmsg("Can't find device: 0x%x\n", rootdev);
 
 	if (opt_writebb == 1) {
 		get_bootblock(bootfile);
@@ -431,7 +400,7 @@ int main(int ac, char **av)
 	if (opt_writembr) {
 		int ffd;
 
-		char *rawtargetdevice = devname(targetdev & ~BIOS_MINOR_MASK);
+		char *rawtargetdevice = devname(targetdev & ~BIOS_MINOR_MASK, S_IFBLK);
 		if (!rawtargetdevice)
 			fatalmsg("Can't find raw target device\n");
 		ffd = open(rawtargetdevice, O_RDWR);
diff --git a/elkscmd/sys_utils/mount.c b/elkscmd/sys_utils/mount.c
index 742ef65f9..4df212e2f 100644
--- a/elkscmd/sys_utils/mount.c
+++ b/elkscmd/sys_utils/mount.c
@@ -13,6 +13,7 @@
 #include <fcntl.h>
 #include <stdlib.h>
 #include <sys/mount.h>
+#include <sys/stat.h>
 #include <linuxmt/fs.h>
 #include <linuxmt/limits.h>
 
@@ -22,47 +23,6 @@ static char *fs_typename[] = {
 	0, "minix", "msdos", "romfs"
 };
 
-static struct dev_name_struct {
-        char *name;
-        dev_t num;
-} devices[] = {
-        /* root_dev_name needs first 5 in order*/
-        { "hda",     0x0300 },
-        { "hdb",     0x0320 },
-        { "hdc",     0x0340 },
-        { "hdd",     0x0360 },
-        { "fd0",     0x0380 },
-        { "fd1",     0x03a0 },
-        { "ssd",     0x0200 },
-        { "rd0",     0x0100 },
-        { "rd1",     0x0101 },
-        { NULL,           0 }
-};
-
-/*
- * Convert a block device number to name.
- */
-static char *dev_name(dev_t dev)
-{
-        int i;
-#define NAMEOFF 5
-        static char name[10] = "/dev/";
-
-        for (i=0; i<sizeof(devices)/sizeof(devices[0])-1; i++) {
-                if (devices[i].num == (dev & 0xfff0)) {
-                        strcpy(&name[NAMEOFF], devices[i].name);
-                        if (i < 4) {
-                                if (dev & 0x07) {
-                                        name[NAMEOFF+3] = '0' + (dev & 7);
-                                        name[NAMEOFF+4] = 0;
-                                }
-                        }
-                        return name;
-                }
-        }
-        return NULL;
-}
-
 static int show_mount(dev_t dev)
 {
 	struct statfs statfs;
@@ -72,11 +32,11 @@ static int show_mount(dev_t dev)
 
 	if (statfs.f_type < FST_MSDOS) 
 		printf("%-9s (%5s) blocks %6lu free %6lu mount %s\n",
-		dev_name(statfs.f_dev), fs_typename[statfs.f_type], statfs.f_blocks,
+		devname(statfs.f_dev, S_IFBLK), fs_typename[statfs.f_type], statfs.f_blocks,
 		statfs.f_bfree, statfs.f_mntonname);
 	else
 		printf("%-9s (%5s)                           mount %s\n",
-		dev_name(statfs.f_dev), fs_typename[statfs.f_type], statfs.f_mntonname);
+		devname(statfs.f_dev, S_IFBLK), fs_typename[statfs.f_type], statfs.f_mntonname);
 	return 0;
 }
 
diff --git a/elkscmd/sys_utils/ps.c b/elkscmd/sys_utils/ps.c
index c03a37303..604605417 100644
--- a/elkscmd/sys_utils/ps.c
+++ b/elkscmd/sys_utils/ps.c
@@ -30,6 +30,7 @@
 #include <dirent.h>
 #include <pwd.h>
 #include <getopt.h>
+#include <paths.h>
 
 #define LINEARADDRESS(off, seg)		((off_t) (((off_t)seg << 4) + off))
 
@@ -69,36 +70,32 @@ void process_name(int fd, unsigned int off, unsigned int seg)
 	}
 }
 
-
-char *devname(unsigned int minor)
+/* fast cached version of devname() */
+char *dev_name(unsigned int minor)
 {
 	struct dirent *d;
 	dev_t ttydev = MKDEV(TTY_MAJOR, minor);
 	static dev_t prevdev = -1;
 	static DIR *fp = NULL;
 	struct stat st;
-	static char dev[] = "/dev";
-	static char name[MAXNAMLEN+1];
+	static char path[MAXNAMLEN+6] = _PATH_DEVSL;    /* /dev/ */
+#define NAMEOFF     (sizeof(_PATH_DEVSL) - 1)
 
-	if (prevdev == ttydev) return name+8;
+	if (prevdev == ttydev) return path+NAMEOFF+3;
 	if (!fp) {
-		if (!(fp = opendir(dev)))
+		if (!(fp = opendir(_PATH_DEV)))
 			return "??";
 	} else rewinddir(fp);
-	strcpy(name, dev);
-	strcat(name, "/");
 
 	while ((d = readdir(fp)) != 0) {
-		if (strlen(d->d_name) > sizeof(name) - sizeof(dev) - 1)
-			continue;
 		if (d->d_name[0] == '.')
 			continue;
 		if (strncmp(d->d_name, "tty", 3))
 			continue;
-		strcpy(name + sizeof(dev), d->d_name);
-		if (!stat(name, &st) && st.st_rdev == ttydev) {
+		strcpy(&path[NAMEOFF], d->d_name);
+		if (!stat(path, &st) && st.st_rdev == ttydev) {
 			prevdev = ttydev;
-			return name+8;
+			return path+NAMEOFF+3;
 		}
 	}
 	return "?";
@@ -115,7 +112,7 @@ char *tty_name(int fd, unsigned int off, unsigned int seg)
 
 	if (read(fd, &tty, sizeof(tty)) != sizeof(tty)) return "?";
 
-	return devname(tty.minor);
+	return dev_name(tty.minor);
 }
 
 int main(int argc, char **argv)
diff --git a/libc/include/limits.h b/libc/include/limits.h
index 49d6e4d11..e8e2d6274 100644
--- a/libc/include/limits.h
+++ b/libc/include/limits.h
@@ -1,18 +1,18 @@
 #ifndef __LIMITS_H
 #define __LIMITS_H
 
+#include <features.h>
+#include __SYSINC__(limits.h)
+
 /* Maximum number of bytes in a pathname, including the terminating null. */
-#define PATH_MAX 128
+#define PATH_MAX        128
 
 /* Maximum number of bytes in a filename, not including terminating null. */
-/* copied from MAXNAMLEN in linuxmt/dirent.h */
-#define NAME_MAX 26
+#define NAME_MAX        MAXNAMLEN
 
-/* copied from PIPE_BUFSIZ in linuxmt/config.h */
-#define PIPE_BUF 80
+#define PIPE_BUF        PIPE_BUFSIZ
 
-/* copied from NR_OPEN in linuxmt/fs.h */
-#define OPEN_MAX 20
+#define OPEN_MAX        NR_OPEN
 
 #ifndef _GCC_NEXT_LIMITS_H
 #include_next <limits.h>
diff --git a/libc/include/paths.h b/libc/include/paths.h
index 668d919ee..4d6415c3b 100644
--- a/libc/include/paths.h
+++ b/libc/include/paths.h
@@ -1,36 +1,34 @@
-/* paths.h <ndf@linux.mit.edu> */
-
 #ifndef ___PATHS_H
-#define	___PATHS_H
-
-
-#define	_PATH_GETTY	"/bin/getty"
-#define	_PATH_LOGIN	"/bin/login"
-#define	_PATH_BSHELL	"/bin/sh"
-#define	_PATH_DEFPATH	"/bin:."
-#define	_PATH_DEV	"/dev"
-#define	_PATH_CONSOLE	"/dev/console"
-#define	_PATH_TTY	"/dev/tty"
-#define _PATH_DEVNULL	"/dev/null"
-#define _PATH_GROUP	"/etc/group"
-#define _PATH_HOSTNAME	"/etc/hostname"
-#define _PATH_INITLVL	"/etc/initlvl"
-#define _PATH_INITTAB	"/etc/inittab"
-#define _PATH_ISSUE	"/etc/issue"
-#define _PATH_MOTD	"/etc/motd"
-#define _PATH_PASSWD	"/etc/passwd"
-#define _PATH_ERRSTRING	"/etc/perror"
-#define _PATH_TERMCAP	"/etc/termcap"
-#define _PATH_LOCALE	"/lib/locale"
-#define _PATH_MANPAGES	"/lib"
-#define	_PATH_TMP	"/tmp"
-#define _PATH_UTMP	"/var/utmp"
-#define _PATH_WTMP	"/var/log/wtmp"
-#define _PATH_LASTLOG	"/var/log/lastlog"
-#define _PATH_DOCBASE	"/var/www"
-#define _PATH_CRONDIR	"/var/cron"
-#define _PATH_CRONTAB	"/var/cron/root"
-#define _PATH_CRONLOG	"/var/cron/cron.log"
+#define ___PATHS_H
+/* paths.h <ndf@linux.mit.edu> */
 
+#define _PATH_GETTY     "/bin/getty"
+#define _PATH_LOGIN     "/bin/login"
+#define _PATH_BSHELL    "/bin/sh"
+#define _PATH_DEFPATH   "/bin:."
+#define _PATH_DEV       "/dev"
+#define _PATH_DEVSL     "/dev/"
+#define _PATH_CONSOLE   "/dev/console"
+#define _PATH_TTY       "/dev/tty"
+#define _PATH_DEVNULL   "/dev/null"
+#define _PATH_GROUP     "/etc/group"
+#define _PATH_HOSTNAME  "/etc/hostname"
+#define _PATH_INITLVL   "/etc/initlvl"
+#define _PATH_INITTAB   "/etc/inittab"
+#define _PATH_ISSUE     "/etc/issue"
+#define _PATH_MOTD      "/etc/motd"
+#define _PATH_PASSWD    "/etc/passwd"
+#define _PATH_ERRSTRING "/etc/perror"
+#define _PATH_TERMCAP   "/etc/termcap"
+#define _PATH_LOCALE    "/lib/locale"
+#define _PATH_MANPAGES  "/lib"
+#define _PATH_TMP       "/tmp"
+#define _PATH_UTMP      "/var/utmp"
+#define _PATH_WTMP      "/var/log/wtmp"
+#define _PATH_LASTLOG   "/var/log/lastlog"
+#define _PATH_DOCBASE   "/var/www"
+#define _PATH_CRONDIR   "/var/cron"
+#define _PATH_CRONTAB   "/var/cron/root"
+#define _PATH_CRONLOG   "/var/cron/cron.log"
 
 #endif /* __PATHS_H */
diff --git a/libc/include/stdlib.h b/libc/include/stdlib.h
index 72a739e07..e76f34006 100644
--- a/libc/include/stdlib.h
+++ b/libc/include/stdlib.h
@@ -1,10 +1,9 @@
-/* stdlib.h  <ndf@linux.mit.edu> */
-#include <features.h>
-#include <sys/types.h>
-
 #ifndef __STDLIB_H
 #define __STDLIB_H
 
+/* stdlib.h  <ndf@linux.mit.edu> */
+#include <features.h>
+#include <sys/types.h>
 #include <malloc.h>
 
 /* Don't overwrite user definitions of NULL */
@@ -59,6 +58,7 @@ void exit (int status);
 int system(const char *command);
 void qsort(void *base, size_t nel, size_t width,
 	int (*compar)(/*const void *, const void * */));
+char *devname(dev_t dev, mode_t type);
 
 #ifndef __STRICT_ANSI__
 void breakpoint();
diff --git a/libc/misc/Makefile b/libc/misc/Makefile
index 5f6f793f9..5b2178862 100644
--- a/libc/misc/Makefile
+++ b/libc/misc/Makefile
@@ -12,6 +12,7 @@ OBJS = \
 	atol.o \
 	basename.o \
 	crypt.o \
+	devname.o \
 	dirname.o \
 	dtostr.o \
 	ecvt.o \
diff --git a/libc/misc/devname.c b/libc/misc/devname.c
new file mode 100644
index 000000000..9a51624fa
--- /dev/null
+++ b/libc/misc/devname.c
@@ -0,0 +1,91 @@
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <paths.h>
+#include <sys/stat.h>
+#include <dirent.h>
+#include __SYSINC__(devnum.h)
+/*
+ * Convert a block or character device number to /dev path.
+ */
+
+#define USE_FASTVERSION 0   /* =1 to use compiled-in device numbers for floppy speed */
+
+static char path[NAME_MAX+6] = _PATH_DEVSL;     /* /dev/ */
+
+#define NAMEOFF         (sizeof(_PATH_DEVSL) - 1)
+#define ARRAYLEN(a)     (sizeof(a)/sizeof(a[0]))
+
+#if USE_FASTVERSION
+static struct dev_name_struct {
+    char *name;
+    mode_t type;
+    dev_t num;
+} devices[] = {
+    /* the 4 partitionable drives must be first */
+    { "hda",     S_IFBLK,   DEV_HDA             },
+    { "hdb",     S_IFBLK,   DEV_HDB             },
+    { "hdc",     S_IFBLK,   DEV_HDC             },
+    { "hdd",     S_IFBLK,   DEV_HDD             },
+    { "fd0",     S_IFBLK,   DEV_FD0             },
+    { "fd1",     S_IFBLK,   DEV_FD1             },
+    { "ssd",     S_IFBLK,   MKDEV(SSD_MAJOR, 0) },
+    { "rd0",     S_IFBLK,   MKDEV(RAM_MAJOR, 0) },
+    { "ttyS0",   S_IFCHR,   DEV_TTYS0           },
+    { "ttyS1",   S_IFCHR,   DEV_TTYS1           },
+    { "tty1",    S_IFCHR,   DEV_TTY1            },
+    { "tty2",    S_IFCHR,   DEV_TTY2            },
+    { "tty3",    S_IFCHR,   DEV_TTY3            },
+};
+
+static char *__fast_devname(dev_t dev, mode_t type)
+{
+    int i;
+    unsigned mask;
+
+    for (i = 0; i < ARRAYLEN(devices); i++) {
+        mask = (i < 4)? 0xfff8: 0xffff;
+        if (devices[i].type == type && devices[i].num == (dev & mask)) {
+            strcpy(&path[NAMEOFF], devices[i].name);
+            if (i < 4) {
+                if (dev & 0x07) {
+                    path[NAMEOFF+3] = '0' + (dev & 7);
+                    path[NAMEOFF+4] = '\0';
+                }
+            }
+            return path;
+        }
+    }
+    return NULL;
+}
+#endif
+
+char *devname(dev_t dev, mode_t type)
+{
+#if USE_FASTVERSION
+    char *s = __fast_devname(dev, type);
+    if (s)
+        return s;
+#endif
+    DIR *dp;
+    struct dirent *d;
+    struct stat st;
+
+    dp = opendir(_PATH_DEV);
+    if (!dp)
+        return NULL;
+
+    while ((d = readdir(dp)) != NULL) {
+        if (d->d_name[0] == '.')
+            continue;
+        strcpy(&path[NAMEOFF], d->d_name);
+        if (stat(path, &st) == 0) {
+            if ((st.st_mode & S_IFMT) == type && st.st_rdev == dev) {
+                closedir(dp);
+                return path;
+            }
+        }
+    }
+    closedir(dp);
+    return NULL;
+}
diff --git a/libc/termios/isatty.c b/libc/termios/isatty.c
index 5afaf5089..5a8bdd77e 100644
--- a/libc/termios/isatty.c
+++ b/libc/termios/isatty.c
@@ -10,8 +10,7 @@ isatty(int fd)
 
 	rv = (ioctl(fd, TCGETS, &term) == 0);
 
-	if(rv == 0
-	&& errno == ENOSYS)
+	if(rv == 0 && errno == ENOSYS)
 		rv = (fd < 3);
 
 	errno = err;
diff --git a/libc/termios/ttyname.c b/libc/termios/ttyname.c
index 225663064..4ad175641 100644
--- a/libc/termios/ttyname.c
+++ b/libc/termios/ttyname.c
@@ -5,45 +5,36 @@
 #include <unistd.h>
 #include <paths.h>
 
-char * ttyname (int fd)
+char *ttyname(int fd)
 {
-   static char dev[] = _PATH_DEV;
-   struct stat st, dst;
-   DIR  *fp;
-   struct dirent *d;
-   static char name[MAXNAMLEN];
-   int noerr = errno;
+    DIR  *dp;
+    struct dirent *d;
+    struct stat src, dst;
+    static char path[MAXNAMLEN+6] = _PATH_DEVSL;     /* /dev/ */
+#define NAMEOFF     (sizeof(_PATH_DEVSL) - 1)
 
-   if (fstat(fd, &st) < 0)
-      return 0;
-   if (!isatty(fd))
-   {
-      errno = ENOTTY;
-      return 0;
-   }
+    if (fstat(fd, &src) < 0)
+        return NULL;
+    if (!isatty(fd)) {
+        errno = ENOTTY;
+        return NULL;
+    }
 
-   fp = opendir(dev);
-   if (fp == 0)
-      return 0;
-   strcpy(name, dev);
-   strcat(name, "/");
+    dp = opendir(_PATH_DEV);
+    if (!dp)
+        return NULL;
 
-   while ((d = readdir(fp)) != 0)
-   {
-      if (strlen(d->d_name) > sizeof(name) - sizeof(dev) - 1)
-         continue;
-      if (d->d_name[0] == '.')
-         continue;
-      strcpy(name + sizeof(dev), d->d_name);
-      if (stat(name, &dst) == 0
-         && st.st_dev == dst.st_dev && st.st_ino == dst.st_ino)
-      {
-         closedir(fp);
-         errno = noerr;
-         return name;
-      }
-   }
-   closedir(fp);
-   errno = noerr;
-   return 0;
+    while ((d = readdir(dp)) != 0) {
+        if (d->d_name[0] == '.')
+            continue;
+        strcpy(&path[NAMEOFF], d->d_name);
+        if (stat(path, &dst) == 0) {
+            if (src.st_dev == dst.st_dev && src.st_ino == dst.st_ino) {
+                closedir(dp);
+                return path;
+            }
+        }
+    }
+    closedir(dp);
+    return NULL;
 }