diff --git a/scanner/fs_darwin.go b/scanner/fs_darwin.go
new file mode 100644
index 0000000..d7c6f22
--- /dev/null
+++ b/scanner/fs_darwin.go
@@ -0,0 +1,31 @@
+// +build darwin
+
+package main
+
+import (
+	"syscall"
+)
+
+func typeToString(name [16]int8) string {
+	var b []byte
+	for _, c := range name {
+		if c == 0 {
+			break
+		}
+		b = append(b, byte(c))
+	}
+	return string(b)
+}
+
+func isNetworkFS(path string) bool {
+	var buf syscall.Statfs_t
+	if err := syscall.Statfs(path, &buf); err != nil {
+		return false
+	}
+	switch typeToString(buf.Fstypename) {
+	case "nfs", "afpfs", "smbfs", "webdav", "devfs":
+		return true
+	default:
+		return false
+	}
+}
diff --git a/scanner/fs_generic.go b/scanner/fs_generic.go
new file mode 100644
index 0000000..d8e0ccd
--- /dev/null
+++ b/scanner/fs_generic.go
@@ -0,0 +1,5 @@
+// +build !linux,!darwin
+
+package main
+
+func isNetworkFS(string) bool { return false }
diff --git a/scanner/fs_linux.go b/scanner/fs_linux.go
new file mode 100644
index 0000000..ee84ad5
--- /dev/null
+++ b/scanner/fs_linux.go
@@ -0,0 +1,147 @@
+// +build linux
+
+package main
+
+import (
+	"syscall"
+)
+
+const (
+	/* statfs(2) */
+	ADFS_SUPER_MAGIC      = 0xadf5
+	AFFS_SUPER_MAGIC      = 0xadff
+	AFS_SUPER_MAGIC       = 0x5346414f
+	ANON_INODE_FS_MAGIC   = 0x09041934
+	AUTOFS_SUPER_MAGIC    = 0x0187
+	BDEVFS_MAGIC          = 0x62646576
+	BEFS_SUPER_MAGIC      = 0x42465331
+	BFS_MAGIC             = 0x1badface
+	BINFMTFS_MAGIC        = 0x42494e4d
+	BPF_FS_MAGIC          = 0xcafe4a11
+	BTRFS_SUPER_MAGIC     = 0x9123683e
+	BTRFS_TEST_MAGIC      = 0x73727279
+	CGROUP_SUPER_MAGIC    = 0x27e0eb
+	CGROUP2_SUPER_MAGIC   = 0x63677270
+	CIFS_MAGIC_NUMBER     = 0xff534d42
+	CODA_SUPER_MAGIC      = 0x73757245
+	COH_SUPER_MAGIC       = 0x012ff7b7
+	CRAMFS_MAGIC          = 0x28cd3d45
+	DEBUGFS_MAGIC         = 0x64626720
+	DEVFS_SUPER_MAGIC     = 0x1373
+	DEVPTS_SUPER_MAGIC    = 0x1cd1
+	ECRYPTFS_SUPER_MAGIC  = 0xf15f
+	EFIVARFS_MAGIC        = 0xde5e81e4
+	EFS_SUPER_MAGIC       = 0x00414a53
+	EXT_SUPER_MAGIC       = 0x137d
+	EXT2_OLD_SUPER_MAGIC  = 0xef51
+	EXT2_SUPER_MAGIC      = 0xef53
+	EXT3_SUPER_MAGIC      = 0xef53
+	EXT4_SUPER_MAGIC      = 0xef53
+	F2FS_SUPER_MAGIC      = 0xf2f52010
+	FUSE_SUPER_MAGIC      = 0x65735546
+	FUTEXFS_SUPER_MAGIC   = 0xbad1dea
+	HFS_SUPER_MAGIC       = 0x4244
+	HOSTFS_SUPER_MAGIC    = 0x00c0ffee
+	HPFS_SUPER_MAGIC      = 0xf995e849
+	HUGETLBFS_MAGIC       = 0x958458f6
+	ISOFS_SUPER_MAGIC     = 0x9660
+	JFFS2_SUPER_MAGIC     = 0x72b6
+	JFS_SUPER_MAGIC       = 0x3153464a
+	MINIX_SUPER_MAGIC     = 0x137f /* orig. minix */
+	MINIX_SUPER_MAGIC2    = 0x138f /* 30 char minix */
+	MINIX2_SUPER_MAGIC    = 0x2468 /* minix V2 */
+	MINIX2_SUPER_MAGIC2   = 0x2478 /* minix V2, 30 char names */
+	MINIX3_SUPER_MAGIC    = 0x4d5a /* minix V3 fs, 60 char names */
+	MQUEUE_MAGIC          = 0x19800202
+	MSDOS_SUPER_MAGIC     = 0x4d44
+	MTD_INODE_FS_MAGIC    = 0x11307854
+	NCP_SUPER_MAGIC       = 0x564c
+	NFS_SUPER_MAGIC       = 0x6969
+	NILFS_SUPER_MAGIC     = 0x3434
+	NSFS_MAGIC            = 0x6e736673
+	NTFS_SB_MAGIC         = 0x5346544e
+	OCFS2_SUPER_MAGIC     = 0x7461636f
+	OPENPROM_SUPER_MAGIC  = 0x9fa1
+	OVERLAYFS_SUPER_MAGIC = 0x794c7630
+	PIPEFS_MAGIC          = 0x50495045
+	PROC_SUPER_MAGIC      = 0x9fa0
+	PSTOREFS_MAGIC        = 0x6165676c
+	QNX4_SUPER_MAGIC      = 0x002f
+	QNX6_SUPER_MAGIC      = 0x68191122
+	RAMFS_MAGIC           = 0x858458f6
+	REISERFS_SUPER_MAGIC  = 0x52654973
+	ROMFS_MAGIC           = 0x7275
+	SECURITYFS_MAGIC      = 0x73636673
+	SELINUX_MAGIC         = 0xf97cff8c
+	SMACK_MAGIC           = 0x43415d53
+	SMB_SUPER_MAGIC       = 0x517b
+	SMB2_MAGIC_NUMBER     = 0xfe534d42
+	SOCKFS_MAGIC          = 0x534f434b
+	SQUASHFS_MAGIC        = 0x73717368
+	SYSFS_MAGIC           = 0x62656572
+	SYSV2_SUPER_MAGIC     = 0x012ff7b6
+	SYSV4_SUPER_MAGIC     = 0x012ff7b5
+	TMPFS_MAGIC           = 0x01021994
+	TRACEFS_MAGIC         = 0x74726163
+	UDF_SUPER_MAGIC       = 0x15013346
+	UFS_MAGIC             = 0x00011954
+	USBDEVICE_SUPER_MAGIC = 0x9fa2
+	V9FS_MAGIC            = 0x01021997
+	VXFS_SUPER_MAGIC      = 0xa501fcf5
+	XENFS_SUPER_MAGIC     = 0xabba1974
+	XENIX_SUPER_MAGIC     = 0x012ff7b4
+	XFS_SUPER_MAGIC       = 0x58465342
+	_XIAFS_SUPER_MAGIC    = 0x012fd16d
+
+	// vmblock.tar:vmblock-only/linux/filesystem.h
+	VMBLOCK_SUPER_MAGIC = 0xabababab
+
+	// linux/fs/afs/super.c
+	AFS_FS_MAGIC = 0x6b414653
+
+	// linux/fs/ceph/super.h
+	CEPH_SUPER_MAGIC = 0x00c36400
+
+	// openafs-1.6.18.2/src/afs/LINUX/osi_vfsops.c
+	OPENAFS_FS_MAGIC = 0x5346414f
+)
+
+func isNetworkFS(path string) bool {
+	var buf syscall.Statfs_t
+	if err := syscall.Statfs(path, &buf); err != nil {
+		return false
+	}
+	switch uint32(buf.Type) {
+	case
+		// pseudo filesystems
+		BDEVFS_MAGIC,
+		BINFMTFS_MAGIC,
+		CGROUP_SUPER_MAGIC,
+		DEBUGFS_MAGIC,
+		EFIVARFS_MAGIC,
+		FUTEXFS_SUPER_MAGIC,
+		HUGETLBFS_MAGIC,
+		PIPEFS_MAGIC,
+		PROC_SUPER_MAGIC,
+		SELINUX_MAGIC,
+		SMACK_MAGIC,
+		SYSFS_MAGIC,
+		// network filesystems
+		AFS_FS_MAGIC,
+		OPENAFS_FS_MAGIC,
+		CEPH_SUPER_MAGIC,
+		CIFS_MAGIC_NUMBER,
+		CODA_SUPER_MAGIC,
+		NCP_SUPER_MAGIC,
+		NFS_SUPER_MAGIC,
+		OCFS2_SUPER_MAGIC,
+		SMB_SUPER_MAGIC,
+		V9FS_MAGIC,
+		VMBLOCK_SUPER_MAGIC,
+		SMB2_MAGIC_NUMBER,
+		XENFS_SUPER_MAGIC:
+		return true
+	default:
+		return false
+	}
+}
diff --git a/scanner/main.go b/scanner/main.go
index 48e1365..b8938c1 100644
--- a/scanner/main.go
+++ b/scanner/main.go
@@ -144,6 +144,12 @@ func main() {
 
 	for _, root := range flag.Args() {
 		filepath.Walk(filepath.Clean(root), func(path string, info os.FileInfo, err error) error {
+			if isNetworkFS(path) {
+				if !quiet {
+					fmt.Fprintf(logFile, "Skipping %s: pseudo or network filesystem\n", path)
+				}
+				return filepath.SkipDir
+			}
 			if !quiet {
 				fmt.Fprintf(logFile, "examining %s\n", path)
 			}
@@ -151,9 +157,9 @@ func main() {
 				fmt.Fprintf(errFile, "%s: %s\n", path, err)
 				return nil
 			}
-			if excludes.Has(path){
+			if excludes.Has(path) {
 				if !quiet {
-					fmt.Fprintf(logFile, "Skipping %s\n", path)
+					fmt.Fprintf(logFile, "Skipping %s: explicitly excluded\n", path)
 				}
 				return filepath.SkipDir
 			}