diff --git a/src/libos/src/syscall/consts.rs b/src/libos/src/syscall/consts.rs
new file mode 100644
index 00000000..781059d1
--- /dev/null
+++ b/src/libos/src/syscall/consts.rs
@@ -0,0 +1,330 @@
+//! Syscall numbers
+
+pub const SYS_READ: u32 = 0;
+pub const SYS_WRITE: u32 = 1;
+pub const SYS_OPEN: u32 = 2;
+pub const SYS_CLOSE: u32 = 3;
+pub const SYS_STAT: u32 = 4;
+pub const SYS_FSTAT: u32 = 5;
+pub const SYS_LSTAT: u32 = 6;
+pub const SYS_POLL: u32 = 7;
+pub const SYS_LSEEK: u32 = 8;
+pub const SYS_MMAP: u32 = 9;
+pub const SYS_MPROTECT: u32 = 10;
+pub const SYS_MUNMAP: u32 = 11;
+pub const SYS_BRK: u32 = 12;
+pub const SYS_RT_SIGACTION: u32 = 13;
+pub const SYS_RT_SIGPROCMASK: u32 = 14;
+pub const SYS_RT_SIGRETURN: u32 = 15;
+pub const SYS_IOCTL: u32 = 16;
+pub const SYS_PREAD64: u32 = 17;
+pub const SYS_PWRITE64: u32 = 18;
+pub const SYS_READV: u32 = 19;
+pub const SYS_WRITEV: u32 = 20;
+pub const SYS_ACCESS: u32 = 21;
+pub const SYS_PIPE: u32 = 22;
+pub const SYS_SELECT: u32 = 23;
+pub const SYS_SCHED_YIELD: u32 = 24;
+pub const SYS_MREMAP: u32 = 25;
+pub const SYS_MSYNC: u32 = 26;
+pub const SYS_MINCORE: u32 = 27;
+pub const SYS_MADVISE: u32 = 28;
+pub const SYS_SHMGET: u32 = 29;
+pub const SYS_SHMAT: u32 = 30;
+pub const SYS_SHMCTL: u32 = 31;
+pub const SYS_DUP: u32 = 32;
+pub const SYS_DUP2: u32 = 33;
+pub const SYS_PAUSE: u32 = 34;
+pub const SYS_NANOSLEEP: u32 = 35;
+pub const SYS_GETITIMER: u32 = 36;
+pub const SYS_ALARM: u32 = 37;
+pub const SYS_SETITIMER: u32 = 38;
+pub const SYS_GETPID: u32 = 39;
+pub const SYS_SENDFILE: u32 = 40;
+pub const SYS_SOCKET: u32 = 41;
+pub const SYS_CONNECT: u32 = 42;
+pub const SYS_ACCEPT: u32 = 43;
+pub const SYS_SENDTO: u32 = 44;
+pub const SYS_RECVFROM: u32 = 45;
+pub const SYS_SENDMSG: u32 = 46;
+pub const SYS_RECVMSG: u32 = 47;
+pub const SYS_SHUTDOWN: u32 = 48;
+pub const SYS_BIND: u32 = 49;
+pub const SYS_LISTEN: u32 = 50;
+pub const SYS_GETSOCKNAME: u32 = 51;
+pub const SYS_GETPEERNAME: u32 = 52;
+pub const SYS_SOCKETPAIR: u32 = 53;
+pub const SYS_SETSOCKOPT: u32 = 54;
+pub const SYS_GETSOCKOPT: u32 = 55;
+pub const SYS_CLONE: u32 = 56;
+pub const SYS_FORK: u32 = 57;
+pub const SYS_VFORK: u32 = 58;
+pub const SYS_EXECVE: u32 = 59;
+pub const SYS_EXIT: u32 = 60;
+pub const SYS_WAIT4: u32 = 61;
+pub const SYS_KILL: u32 = 62;
+pub const SYS_UNAME: u32 = 63;
+pub const SYS_SEMGET: u32 = 64;
+pub const SYS_SEMOP: u32 = 65;
+pub const SYS_SEMCTL: u32 = 66;
+pub const SYS_SHMDT: u32 = 67;
+pub const SYS_MSGGET: u32 = 68;
+pub const SYS_MSGSND: u32 = 69;
+pub const SYS_MSGRCV: u32 = 70;
+pub const SYS_MSGCTL: u32 = 71;
+pub const SYS_FCNTL: u32 = 72;
+pub const SYS_FLOCK: u32 = 73;
+pub const SYS_FSYNC: u32 = 74;
+pub const SYS_FDATASYNC: u32 = 75;
+pub const SYS_TRUNCATE: u32 = 76;
+pub const SYS_FTRUNCATE: u32 = 77;
+pub const SYS_GETDENTS: u32 = 78;
+pub const SYS_GETCWD: u32 = 79;
+pub const SYS_CHDIR: u32 = 80;
+pub const SYS_FCHDIR: u32 = 81;
+pub const SYS_RENAME: u32 = 82;
+pub const SYS_MKDIR: u32 = 83;
+pub const SYS_RMDIR: u32 = 84;
+pub const SYS_CREAT: u32 = 85;
+pub const SYS_LINK: u32 = 86;
+pub const SYS_UNLINK: u32 = 87;
+pub const SYS_SYMLINK: u32 = 88;
+pub const SYS_READLINK: u32 = 89;
+pub const SYS_CHMOD: u32 = 90;
+pub const SYS_FCHMOD: u32 = 91;
+pub const SYS_CHOWN: u32 = 92;
+pub const SYS_FCHOWN: u32 = 93;
+pub const SYS_LCHOWN: u32 = 94;
+pub const SYS_UMASK: u32 = 95;
+pub const SYS_GETTIMEOFDAY: u32 = 96;
+pub const SYS_GETRLIMIT: u32 = 97;
+pub const SYS_GETRUSAGE: u32 = 98;
+pub const SYS_SYSINFO: u32 = 99;
+pub const SYS_TIMES: u32 = 100;
+pub const SYS_PTRACE: u32 = 101;
+pub const SYS_GETUID: u32 = 102;
+pub const SYS_SYSLOG: u32 = 103;
+pub const SYS_GETGID: u32 = 104;
+pub const SYS_SETUID: u32 = 105;
+pub const SYS_SETGID: u32 = 106;
+pub const SYS_GETEUID: u32 = 107;
+pub const SYS_GETEGID: u32 = 108;
+pub const SYS_SETPGID: u32 = 109;
+pub const SYS_GETPPID: u32 = 110;
+pub const SYS_GETPGRP: u32 = 111;
+pub const SYS_SETSID: u32 = 112;
+pub const SYS_SETREUID: u32 = 113;
+pub const SYS_SETREGID: u32 = 114;
+pub const SYS_GETGROUPS: u32 = 115;
+pub const SYS_SETGROUPS: u32 = 116;
+pub const SYS_SETRESUID: u32 = 117;
+pub const SYS_GETRESUID: u32 = 118;
+pub const SYS_SETRESGID: u32 = 119;
+pub const SYS_GETRESGID: u32 = 120;
+pub const SYS_GETPGID: u32 = 121;
+pub const SYS_SETFSUID: u32 = 122;
+pub const SYS_SETFSGID: u32 = 123;
+pub const SYS_GETSID: u32 = 124;
+pub const SYS_CAPGET: u32 = 125;
+pub const SYS_CAPSET: u32 = 126;
+pub const SYS_RT_SIGPENDING: u32 = 127;
+pub const SYS_RT_SIGTIMEDWAIT: u32 = 128;
+pub const SYS_RT_SIGQUEUEINFO: u32 = 129;
+pub const SYS_RT_SIGSUSPEND: u32 = 130;
+pub const SYS_SIGALTSTACK: u32 = 131;
+pub const SYS_UTIME: u32 = 132;
+pub const SYS_MKNOD: u32 = 133;
+pub const SYS_USELIB: u32 = 134;
+pub const SYS_PERSONALITY: u32 = 135;
+pub const SYS_USTAT: u32 = 136;
+pub const SYS_STATFS: u32 = 137;
+pub const SYS_FSTATFS: u32 = 138;
+pub const SYS_SYSFS: u32 = 139;
+pub const SYS_GETPRIORITY: u32 = 140;
+pub const SYS_SETPRIORITY: u32 = 141;
+pub const SYS_SCHED_SETPARAM: u32 = 142;
+pub const SYS_SCHED_GETPARAM: u32 = 143;
+pub const SYS_SCHED_SETSCHEDULER: u32 = 144;
+pub const SYS_SCHED_GETSCHEDULER: u32 = 145;
+pub const SYS_SCHED_GET_PRIORITY_MAX: u32 = 146;
+pub const SYS_SCHED_GET_PRIORITY_MIN: u32 = 147;
+pub const SYS_SCHED_RR_GET_INTERVAL: u32 = 148;
+pub const SYS_MLOCK: u32 = 149;
+pub const SYS_MUNLOCK: u32 = 150;
+pub const SYS_MLOCKALL: u32 = 151;
+pub const SYS_MUNLOCKALL: u32 = 152;
+pub const SYS_VHANGUP: u32 = 153;
+pub const SYS_MODIFY_LDT: u32 = 154;
+pub const SYS_PIVOT_ROOT: u32 = 155;
+pub const SYS__SYSCTL: u32 = 156;
+pub const SYS_PRCTL: u32 = 157;
+pub const SYS_ARCH_PRCTL: u32 = 158;
+pub const SYS_ADJTIMEX: u32 = 159;
+pub const SYS_SETRLIMIT: u32 = 160;
+pub const SYS_CHROOT: u32 = 161;
+pub const SYS_SYNC: u32 = 162;
+pub const SYS_ACCT: u32 = 163;
+pub const SYS_SETTIMEOFDAY: u32 = 164;
+pub const SYS_MOUNT: u32 = 165;
+pub const SYS_UMOUNT2: u32 = 166;
+pub const SYS_SWAPON: u32 = 167;
+pub const SYS_SWAPOFF: u32 = 168;
+pub const SYS_REBOOT: u32 = 169;
+pub const SYS_SETHOSTNAME: u32 = 170;
+pub const SYS_SETDOMAINNAME: u32 = 171;
+pub const SYS_IOPL: u32 = 172;
+pub const SYS_IOPERM: u32 = 173;
+pub const SYS_CREATE_MODULE: u32 = 174;
+pub const SYS_INIT_MODULE: u32 = 175;
+pub const SYS_DELETE_MODULE: u32 = 176;
+pub const SYS_GET_KERNEL_SYMS: u32 = 177;
+pub const SYS_QUERY_MODULE: u32 = 178;
+pub const SYS_QUOTACTL: u32 = 179;
+pub const SYS_NFSSERVCTL: u32 = 180;
+pub const SYS_GETPMSG: u32 = 181;
+pub const SYS_PUTPMSG: u32 = 182;
+pub const SYS_AFS_SYSCALL: u32 = 183;
+pub const SYS_TUXCALL: u32 = 184;
+pub const SYS_SECURITY: u32 = 185;
+pub const SYS_GETTID: u32 = 186;
+pub const SYS_READAHEAD: u32 = 187;
+pub const SYS_SETXATTR: u32 = 188;
+pub const SYS_LSETXATTR: u32 = 189;
+pub const SYS_FSETXATTR: u32 = 190;
+pub const SYS_GETXATTR: u32 = 191;
+pub const SYS_LGETXATTR: u32 = 192;
+pub const SYS_FGETXATTR: u32 = 193;
+pub const SYS_LISTXATTR: u32 = 194;
+pub const SYS_LLISTXATTR: u32 = 195;
+pub const SYS_FLISTXATTR: u32 = 196;
+pub const SYS_REMOVEXATTR: u32 = 197;
+pub const SYS_LREMOVEXATTR: u32 = 198;
+pub const SYS_FREMOVEXATTR: u32 = 199;
+pub const SYS_TKILL: u32 = 200;
+pub const SYS_TIME: u32 = 201;
+pub const SYS_FUTEX: u32 = 202;
+pub const SYS_SCHED_SETAFFINITY: u32 = 203;
+pub const SYS_SCHED_GETAFFINITY: u32 = 204;
+pub const SYS_SET_THREAD_AREA: u32 = 205;
+pub const SYS_IO_SETUP: u32 = 206;
+pub const SYS_IO_DESTROY: u32 = 207;
+pub const SYS_IO_GETEVENTS: u32 = 208;
+pub const SYS_IO_SUBMIT: u32 = 209;
+pub const SYS_IO_CANCEL: u32 = 210;
+pub const SYS_GET_THREAD_AREA: u32 = 211;
+pub const SYS_LOOKUP_DCOOKIE: u32 = 212;
+pub const SYS_EPOLL_CREATE: u32 = 213;
+pub const SYS_EPOLL_CTL_OLD: u32 = 214;
+pub const SYS_EPOLL_WAIT_OLD: u32 = 215;
+pub const SYS_REMAP_FILE_PAGES: u32 = 216;
+pub const SYS_GETDENTS64: u32 = 217;
+pub const SYS_SET_TID_ADDRESS: u32 = 218;
+pub const SYS_RESTART_SYSCALL: u32 = 219;
+pub const SYS_SEMTIMEDOP: u32 = 220;
+pub const SYS_FADVISE64: u32 = 221;
+pub const SYS_TIMER_CREATE: u32 = 222;
+pub const SYS_TIMER_SETTIME: u32 = 223;
+pub const SYS_TIMER_GETTIME: u32 = 224;
+pub const SYS_TIMER_GETOVERRUN: u32 = 225;
+pub const SYS_TIMER_DELETE: u32 = 226;
+pub const SYS_CLOCK_SETTIME: u32 = 227;
+pub const SYS_CLOCK_GETTIME: u32 = 228;
+pub const SYS_CLOCK_GETRES: u32 = 229;
+pub const SYS_CLOCK_NANOSLEEP: u32 = 230;
+pub const SYS_EXIT_GROUP: u32 = 231;
+pub const SYS_EPOLL_WAIT: u32 = 232;
+pub const SYS_EPOLL_CTL: u32 = 233;
+pub const SYS_TGKILL: u32 = 234;
+pub const SYS_UTIMES: u32 = 235;
+pub const SYS_VSERVER: u32 = 236;
+pub const SYS_MBIND: u32 = 237;
+pub const SYS_SET_MEMPOLICY: u32 = 238;
+pub const SYS_GET_MEMPOLICY: u32 = 239;
+pub const SYS_MQ_OPEN: u32 = 240;
+pub const SYS_MQ_UNLINK: u32 = 241;
+pub const SYS_MQ_TIMEDSEND: u32 = 242;
+pub const SYS_MQ_TIMEDRECEIVE: u32 = 243;
+pub const SYS_MQ_NOTIFY: u32 = 244;
+pub const SYS_MQ_GETSETATTR: u32 = 245;
+pub const SYS_KEXEC_LOAD: u32 = 246;
+pub const SYS_WAITID: u32 = 247;
+pub const SYS_ADD_KEY: u32 = 248;
+pub const SYS_REQUEST_KEY: u32 = 249;
+pub const SYS_KEYCTL: u32 = 250;
+pub const SYS_IOPRIO_SET: u32 = 251;
+pub const SYS_IOPRIO_GET: u32 = 252;
+pub const SYS_INOTIFY_INIT: u32 = 253;
+pub const SYS_INOTIFY_ADD_WATCH: u32 = 254;
+pub const SYS_INOTIFY_RM_WATCH: u32 = 255;
+pub const SYS_MIGRATE_PAGES: u32 = 256;
+pub const SYS_OPENAT: u32 = 257;
+pub const SYS_MKDIRAT: u32 = 258;
+pub const SYS_MKNODAT: u32 = 259;
+pub const SYS_FCHOWNAT: u32 = 260;
+pub const SYS_FUTIMESAT: u32 = 261;
+pub const SYS_NEWFSTATAT: u32 = 262;
+pub const SYS_UNLINKAT: u32 = 263;
+pub const SYS_RENAMEAT: u32 = 264;
+pub const SYS_LINKAT: u32 = 265;
+pub const SYS_SYMLINKAT: u32 = 266;
+pub const SYS_READLINKAT: u32 = 267;
+pub const SYS_FCHMODAT: u32 = 268;
+pub const SYS_FACCESSAT: u32 = 269;
+pub const SYS_PSELECT6: u32 = 270;
+pub const SYS_PPOLL: u32 = 271;
+pub const SYS_UNSHARE: u32 = 272;
+pub const SYS_SET_ROBUST_LIST: u32 = 273;
+pub const SYS_GET_ROBUST_LIST: u32 = 274;
+pub const SYS_SPLICE: u32 = 275;
+pub const SYS_TEE: u32 = 276;
+pub const SYS_SYNC_FILE_RANGE: u32 = 277;
+pub const SYS_VMSPLICE: u32 = 278;
+pub const SYS_MOVE_PAGES: u32 = 279;
+pub const SYS_UTIMENSAT: u32 = 280;
+pub const SYS_EPOLL_PWAIT: u32 = 281;
+pub const SYS_SIGNALFD: u32 = 282;
+pub const SYS_TIMERFD_CREATE: u32 = 283;
+pub const SYS_EVENTFD: u32 = 284;
+pub const SYS_FALLOCATE: u32 = 285;
+pub const SYS_TIMERFD_SETTIME: u32 = 286;
+pub const SYS_TIMERFD_GETTIME: u32 = 287;
+pub const SYS_ACCEPT4: u32 = 288;
+pub const SYS_SIGNALFD4: u32 = 289;
+pub const SYS_EVENTFD2: u32 = 290;
+pub const SYS_EPOLL_CREATE1: u32 = 291;
+pub const SYS_DUP3: u32 = 292;
+pub const SYS_PIPE2: u32 = 293;
+pub const SYS_INOTIFY_INIT1: u32 = 294;
+pub const SYS_PREADV: u32 = 295;
+pub const SYS_PWRITEV: u32 = 296;
+pub const SYS_RT_TGSIGQUEUEINFO: u32 = 297;
+pub const SYS_PERF_EVENT_OPEN: u32 = 298;
+pub const SYS_RECVMMSG: u32 = 299;
+pub const SYS_FANOTIFY_INIT: u32 = 300;
+pub const SYS_FANOTIFY_MARK: u32 = 301;
+pub const SYS_PRLIMIT64: u32 = 302;
+pub const SYS_NAME_TO_HANDLE_AT: u32 = 303;
+pub const SYS_OPEN_BY_HANDLE_AT: u32 = 304;
+pub const SYS_CLOCK_ADJTIME: u32 = 305;
+pub const SYS_SYNCFS: u32 = 306;
+pub const SYS_SENDMMSG: u32 = 307;
+pub const SYS_SETNS: u32 = 308;
+pub const SYS_GETCPU: u32 = 309;
+pub const SYS_PROCESS_VM_READV: u32 = 310;
+pub const SYS_PROCESS_VM_WRITEV: u32 = 311;
+pub const SYS_KCMP: u32 = 312;
+pub const SYS_FINIT_MODULE: u32 = 313;
+pub const SYS_SCHED_SETATTR: u32 = 314;
+pub const SYS_SCHED_GETATTR: u32 = 315;
+pub const SYS_RENAMEAT2: u32 = 316;
+pub const SYS_SECCOMP: u32 = 317;
+pub const SYS_GETRANDOM: u32 = 318;
+pub const SYS_MEMFD_CREATE: u32 = 319;
+pub const SYS_KEXEC_FILE_LOAD: u32 = 320;
+pub const SYS_BPF: u32 = 321;
+pub const SYS_EXECVEAT: u32 = 322;
+pub const SYS_USERFAULTFD: u32 = 323;
+pub const SYS_MEMBARRIER: u32 = 324;
+pub const SYS_MLOCK2: u32 = 325;
+
+pub const SYS_SPAWN: u32 = 360;
diff --git a/src/libos/src/syscall/mod.rs b/src/libos/src/syscall/mod.rs
index 62eeabed..27d2431c 100644
--- a/src/libos/src/syscall/mod.rs
+++ b/src/libos/src/syscall/mod.rs
@@ -12,9 +12,13 @@ use {fs, process, std, vm};
 //use std::libc_fs as fs;
 //use std::libc_io as io;
 
+use self::consts::*;
 use fs::File;
 
+mod consts;
+
 #[no_mangle]
+#[deny(unreachable_patterns)]
 pub extern "C" fn dispatch_syscall(
     num: u32,
     arg0: isize,
@@ -26,37 +30,37 @@ pub extern "C" fn dispatch_syscall(
 ) -> isize {
     debug!("syscall {}: {:#x}, {:#x}, {:#x}, {:#x}, {:#x}, {:#x}", num, arg0, arg1, arg2, arg3, arg4, arg5);
     let ret = match num {
-        002 => do_open(arg0 as *const i8, arg1 as u32, arg2 as u32),
-        003 => do_close(arg0 as FileDesc),
-        000 => do_read(arg0 as FileDesc, arg1 as *mut u8, arg2 as usize),
-        001 => do_write(arg0 as FileDesc, arg1 as *const u8, arg2 as usize),
-        019 => do_readv(arg0 as FileDesc, arg1 as *mut iovec_t, arg2 as i32),
-        020 => do_writev(arg0 as FileDesc, arg1 as *mut iovec_t, arg2 as i32),
-        004 => do_stat(arg0 as *const i8, arg1 as *mut fs::Stat),
-        005 => do_fstat(arg0 as FileDesc, arg1 as *mut fs::Stat),
-        006 => do_lstat(arg0 as *const i8, arg1 as *mut fs::Stat),
-        008 => do_lseek(arg0 as FileDesc, arg1 as off_t, arg2 as i32),
-        074 => do_fsync(arg0 as FileDesc),
-        075 => do_fdatasync(arg0 as FileDesc),
-        076 => do_truncate(arg0 as *const i8, arg1 as usize),
-        077 => do_ftruncate(arg0 as FileDesc, arg1 as usize),
-        217 => do_getdents64(arg0 as FileDesc, arg1 as *mut u8, arg2 as usize),
-        162 => do_sync(),
-        079 => do_getcwd(arg0 as *mut u8, arg1 as usize),
+        SYS_OPEN => do_open(arg0 as *const i8, arg1 as u32, arg2 as u32),
+        SYS_CLOSE => do_close(arg0 as FileDesc),
+        SYS_READ => do_read(arg0 as FileDesc, arg1 as *mut u8, arg2 as usize),
+        SYS_WRITE => do_write(arg0 as FileDesc, arg1 as *const u8, arg2 as usize),
+        SYS_READV => do_readv(arg0 as FileDesc, arg1 as *mut iovec_t, arg2 as i32),
+        SYS_WRITEV => do_writev(arg0 as FileDesc, arg1 as *mut iovec_t, arg2 as i32),
+        SYS_STAT => do_stat(arg0 as *const i8, arg1 as *mut fs::Stat),
+        SYS_FSTAT => do_fstat(arg0 as FileDesc, arg1 as *mut fs::Stat),
+        SYS_LSTAT => do_lstat(arg0 as *const i8, arg1 as *mut fs::Stat),
+        SYS_LSEEK => do_lseek(arg0 as FileDesc, arg1 as off_t, arg2 as i32),
+        SYS_FSYNC => do_fsync(arg0 as FileDesc),
+        SYS_FDATASYNC => do_fdatasync(arg0 as FileDesc),
+        SYS_TRUNCATE => do_truncate(arg0 as *const i8, arg1 as usize),
+        SYS_FTRUNCATE => do_ftruncate(arg0 as FileDesc, arg1 as usize),
+        SYS_GETDENTS64 => do_getdents64(arg0 as FileDesc, arg1 as *mut u8, arg2 as usize),
+        SYS_SYNC => do_sync(),
+        SYS_GETCWD => do_getcwd(arg0 as *mut u8, arg1 as usize),
 
-        060 => do_exit(arg0 as i32),
-        360 => do_spawn(
+        SYS_EXIT => do_exit(arg0 as i32),
+        SYS_SPAWN => do_spawn(
             arg0 as *mut u32,
             arg1 as *mut i8,
             arg2 as *const *const i8,
             arg3 as *const *const i8,
             arg4 as *const FdOp,
         ),
-        061 => do_wait4(arg0 as i32, arg1 as *mut i32),
-        039 => do_getpid(),
-        110 => do_getppid(),
+        SYS_WAIT4 => do_wait4(arg0 as i32, arg1 as *mut i32),
+        SYS_GETPID => do_getpid(),
+        SYS_GETPPID => do_getppid(),
 
-        009 => do_mmap(
+        SYS_MMAP => do_mmap(
             arg0 as usize,
             arg1 as usize,
             arg2 as i32,
@@ -64,23 +68,23 @@ pub extern "C" fn dispatch_syscall(
             arg4 as FileDesc,
             arg5 as off_t,
         ),
-        011 => do_munmap(arg0 as usize, arg1 as usize),
-        025 => do_mremap(
+        SYS_MUNMAP => do_munmap(arg0 as usize, arg1 as usize),
+        SYS_MREMAP => do_mremap(
             arg0 as usize,
             arg1 as usize,
             arg2 as usize,
             arg3 as i32,
             arg4 as usize,
         ),
-        012 => do_brk(arg0 as usize),
+        SYS_BRK => do_brk(arg0 as usize),
 
-        022 => do_pipe2(arg0 as *mut i32, 0),
-        293 => do_pipe2(arg0 as *mut i32, arg1 as u32),
-        032 => do_dup(arg0 as FileDesc),
-        033 => do_dup2(arg0 as FileDesc, arg1 as FileDesc),
-        292 => do_dup3(arg0 as FileDesc, arg1 as FileDesc, arg2 as u32),
+        SYS_PIPE => do_pipe2(arg0 as *mut i32, 0),
+        SYS_PIPE2 => do_pipe2(arg0 as *mut i32, arg1 as u32),
+        SYS_DUP => do_dup(arg0 as FileDesc),
+        SYS_DUP2 => do_dup2(arg0 as FileDesc, arg1 as FileDesc),
+        SYS_DUP3 => do_dup3(arg0 as FileDesc, arg1 as FileDesc, arg2 as u32),
 
-        096 => do_gettimeofday(arg0 as *mut timeval_t),
+        SYS_GETTIMEOFDAY => do_gettimeofday(arg0 as *mut timeval_t),
 
         _ => do_unknown(num),
     };
@@ -174,13 +178,11 @@ fn do_open(path: *const i8, flags: u32, mode: u32) -> Result<isize, Error> {
 }
 
 fn do_close(fd: FileDesc) -> Result<isize, Error> {
-    info!("close: fd: {}", fd);
     fs::do_close(fd)?;
     Ok(0)
 }
 
 fn do_read(fd: FileDesc, buf: *mut u8, size: usize) -> Result<isize, Error> {
-    info!("write: fd: {}, buf: {:?}, size: {}", fd, buf, size);
     let safe_buf = {
         check_mut_array(buf, size)?;
         unsafe { std::slice::from_raw_parts_mut(buf, size) }
@@ -190,7 +192,6 @@ fn do_read(fd: FileDesc, buf: *mut u8, size: usize) -> Result<isize, Error> {
 }
 
 fn do_write(fd: FileDesc, buf: *const u8, size: usize) -> Result<isize, Error> {
-    info!("write: fd: {}, buf: {:?}, size: {}", fd, buf, size);
     let safe_buf = {
         check_array(buf, size)?;
         unsafe { std::slice::from_raw_parts(buf, size) }
@@ -404,7 +405,6 @@ fn do_wait4(pid: i32, _exit_status: *mut i32) -> Result<isize, Error> {
 }
 
 fn do_getpid() -> Result<isize, Error> {
-    info!("getpid");
     let pid = process::do_getpid();
     Ok(pid as isize)
 }
@@ -454,7 +454,6 @@ fn do_gettimeofday(tv_u: *mut timeval_t) -> Result<isize, Error> {
 const MAP_FAILED: *const c_void = ((-1) as i64) as *const c_void;
 
 fn do_exit(status: i32) -> ! {
-    info!("exit: {}", status);
     extern "C" {
         fn do_exit_task() -> !;
     }
@@ -465,7 +464,9 @@ fn do_exit(status: i32) -> ! {
 }
 
 fn do_unknown(num: u32) -> Result<isize, Error> {
-    warn!("Unknown syscall (num = {})", num);
+    if cfg!(debug_assertions) {
+        //println!("[WARNING] Unknown syscall (num = {})", num);
+    }
     Err(Error::new(ENOSYS, "Unknown syscall"))
 }