diff --git a/src/lib/libsigs.js b/src/lib/libsigs.js
index 60dce773943be..b7c6de207248b 100644
--- a/src/lib/libsigs.js
+++ b/src/lib/libsigs.js
@@ -231,10 +231,10 @@ sigs = {
   __pthread_create_js__sig: 'ipppp',
   __resumeException__sig: 'vp',
   __syscall_accept4__sig: 'iippiii',
-  __syscall_bind__sig: 'iippiii',
+  __syscall_bind__sig: 'iipiiii',
   __syscall_chdir__sig: 'ip',
   __syscall_chmod__sig: 'ipi',
-  __syscall_connect__sig: 'iippiii',
+  __syscall_connect__sig: 'iipiiii',
   __syscall_dup__sig: 'ii',
   __syscall_dup3__sig: 'iiii',
   __syscall_faccessat__sig: 'iipii',
@@ -265,12 +265,12 @@ sigs = {
   __syscall_poll__sig: 'ipii',
   __syscall_poll_nonblocking__sig: 'ipi',
   __syscall_readlinkat__sig: 'iippp',
-  __syscall_recvfrom__sig: 'iippipp',
-  __syscall_recvmsg__sig: 'iipiiii',
+  __syscall_recvfrom__sig: 'pippipp',
+  __syscall_recvmsg__sig: 'pipiiii',
   __syscall_renameat__sig: 'iipip',
   __syscall_rmdir__sig: 'ip',
-  __syscall_sendmsg__sig: 'iipippi',
-  __syscall_sendto__sig: 'iippipp',
+  __syscall_sendmsg__sig: 'pipippi',
+  __syscall_sendto__sig: 'pippipi',
   __syscall_shutdown__sig: 'iiiiiii',
   __syscall_socket__sig: 'iiiiiii',
   __syscall_stat64__sig: 'ipp',
diff --git a/system/include/emscripten/syscalls.h b/system/include/emscripten/syscalls.h
index 336d6a8d5ddd3..521d65db58d46 100644
--- a/system/include/emscripten/syscalls.h
+++ b/system/include/emscripten/syscalls.h
@@ -7,8 +7,10 @@
 
 #pragma once
 
+#include <poll.h>
 #include <stddef.h>
 #include <stdint.h>
+#include <sys/socket.h>
 #include <sys/types.h>
 
 #ifdef __cplusplus
@@ -16,42 +18,42 @@ extern "C" {
 #endif
 
 int __syscall_chdir(intptr_t path);
-int __syscall_mknod(intptr_t path, int mode, int dev);
-int __syscall_chmod(intptr_t path, int mode);
-int __syscall_getpid(void);
+int __syscall_mknod(intptr_t path, mode_t mode, dev_t dev);
+int __syscall_chmod(intptr_t path, mode_t mode);
+pid_t __syscall_getpid(void);
 int __syscall_access(intptr_t path, int amode);
 int __syscall_sync(void);
 int __syscall_rmdir(intptr_t path);
 int __syscall_dup(int fd);
 int __syscall_acct(intptr_t filename);
 int __syscall_ioctl(int fd, int request, ...);
-int __syscall_setpgid(int pid, int gpid);
-int __syscall_umask(int mask);
-int __syscall_getppid(void);
-int __syscall_getpgrp(void);
-int __syscall_setsid(void);
+int __syscall_setpgid(pid_t pid, pid_t gpid);
+mode_t __syscall_umask(mode_t mask);
+pid_t __syscall_getppid(void);
+pid_t __syscall_getpgrp(void);
+pid_t __syscall_setsid(void);
 int __syscall_getrusage(int who, intptr_t usage);
 int __syscall_munmap(intptr_t addr, size_t len);
-int __syscall_fchmod(int fd, int mode);
-int __syscall_getpriority(int which, int who);
-int __syscall_setpriority(int which, int who, int prio);
+int __syscall_fchmod(int fd, mode_t mode);
+int __syscall_getpriority(int which, id_t who);
+int __syscall_setpriority(int which, id_t who, int prio);
 int __syscall_socketcall(int call, intptr_t args);
-int __syscall_wait4(int pid, intptr_t wstatus, int options, int rusage);
+pid_t __syscall_wait4(pid_t pid, intptr_t wstatus, int options, int rusage);
 int __syscall_setdomainname(intptr_t name, size_t size);
 int __syscall_uname(intptr_t buf);
 int __syscall_mprotect(size_t addr, size_t len, int prot);
-int __syscall_getpgid(int pid);
+pid_t __syscall_getpgid(pid_t pid);
 int __syscall_fchdir(int fd);
 int __syscall_msync(intptr_t addr, size_t len, int flags);
-int __syscall_getsid(int pid);
+pid_t __syscall_getsid(pid_t pid);
 int __syscall_fdatasync(int fd);
 int __syscall_mlock(intptr_t addr, size_t len);
 int __syscall_munlock(intptr_t addr, size_t len);
 int __syscall_mlockall(int flags);
 int __syscall_munlockall(void);
 int __syscall_mremap(intptr_t old_addr, size_t old_size, size_t new_size, int flags, intptr_t new_addr);
-int __syscall_poll(intptr_t fds, int nfds, int timeout);
-int __syscall_poll_nonblocking(intptr_t fds, int nfds);
+int __syscall_poll(intptr_t fds, nfds_t nfds, int timeout);
+int __syscall_poll_nonblocking(intptr_t fds, nfds_t nfds);
 int __syscall_getcwd(intptr_t buf, size_t size);
 intptr_t __syscall_mmap2(intptr_t addr, size_t len, int prot, int flags, int fd, off_t offset);
 int __syscall_truncate64(intptr_t path, off_t length);
@@ -59,20 +61,20 @@ int __syscall_ftruncate64(int fd, off_t length);
 int __syscall_stat64(intptr_t path, intptr_t buf);
 int __syscall_lstat64(intptr_t path, intptr_t buf);
 int __syscall_fstat64(int fd, intptr_t buf);
-int __syscall_getuid32(void);
-int __syscall_getgid32(void);
-int __syscall_geteuid32(void);
-int __syscall_getegid32(void);
-int __syscall_setreuid32(int ruid, int euid);
-int __syscall_setregid32(int rgid, int egid);
-int __syscall_getgroups32(int size, intptr_t list);
-int __syscall_fchown32(int fd, int owner, int group);
-int __syscall_setresuid32(int ruid, int euid, int suid);
+uid_t __syscall_getuid32(void);
+gid_t __syscall_getgid32(void);
+uid_t __syscall_geteuid32(void);
+gid_t __syscall_getegid32(void);
+int __syscall_setreuid32(uid_t ruid, uid_t euid);
+int __syscall_setregid32(gid_t rgid, gid_t egid);
+int __syscall_getgroups32(int count, intptr_t list);
+int __syscall_fchown32(int fd, uid_t owner, gid_t group);
+int __syscall_setresuid32(uid_t ruid, uid_t euid, uid_t suid);
 int __syscall_getresuid32(intptr_t ruid, intptr_t euid, intptr_t suid);
-int __syscall_setresgid32(int rgid, int egid, int sgid);
+int __syscall_setresgid32(gid_t rgid, gid_t egid, gid_t sgid);
 int __syscall_getresgid32(intptr_t rgid, intptr_t egid, intptr_t sgid);
-int __syscall_setuid32(int uid);
-int __syscall_setgid32(int uid);
+int __syscall_setuid32(uid_t uid);
+int __syscall_setgid32(gid_t gid);
 int __syscall_mincore(intptr_t addr, size_t length, intptr_t vec);
 int __syscall_madvise(intptr_t addr, size_t length, int advice);
 int __syscall_getdents64(int fd, intptr_t dirp, size_t count);
@@ -81,38 +83,38 @@ int __syscall_statfs64(intptr_t path, size_t size, intptr_t buf);
 int __syscall_fstatfs64(int fd, size_t size, intptr_t buf);
 int __syscall_fadvise64(int fd, off_t offset, off_t length, int advice);
 int __syscall_openat(int dirfd, intptr_t path, int flags, ...); // mode is optional
-int __syscall_mkdirat(int dirfd, intptr_t path, int mode);
-int __syscall_mknodat(int dirfd, intptr_t path, int mode, int dev);
-int __syscall_fchownat(int dirfd, intptr_t path, int owner, int group, int flags);
+int __syscall_mkdirat(int dirfd, intptr_t path, mode_t mode);
+int __syscall_mknodat(int dirfd, intptr_t path, mode_t mode, dev_t dev);
+int __syscall_fchownat(int dirfd, intptr_t path, uid_t owner, gid_t group, int flags);
 int __syscall_newfstatat(int dirfd, intptr_t path, intptr_t buf, int flags);
 int __syscall_unlinkat(int dirfd, intptr_t path, int flags);
 int __syscall_renameat(int olddirfd, intptr_t oldpath, int newdirfd, intptr_t newpath);
 int __syscall_linkat(int olddirfd, intptr_t oldpath, int newdirfd, intptr_t newpath, int flags);
 int __syscall_symlinkat(intptr_t target, int newdirfd, intptr_t linkpath);
 int __syscall_readlinkat(int dirfd, intptr_t path, intptr_t buf, size_t bufsize);
-int __syscall_fchmodat2(int dirfd, intptr_t path, int mode, int flags);
+int __syscall_fchmodat2(int dirfd, intptr_t path, mode_t mode, int flags);
 int __syscall_faccessat(int dirfd, intptr_t path, int amode, int flags);
 int __syscall_utimensat(int dirfd, intptr_t path, intptr_t times, int flags);
 int __syscall_fallocate(int fd, int mode, off_t offset, off_t len);
 int __syscall_dup3(int fd, int suggestfd, int flags);
 int __syscall_pipe2(intptr_t fds, int flags);
-int __syscall_recvmmsg(int sockfd, intptr_t msgvec, size_t vlen, int flags, ...);
-int __syscall_prlimit64(int pid, int resource, intptr_t new_limit, intptr_t old_limit);
-int __syscall_sendmmsg(int sockfd, intptr_t msgvec, size_t vlen, int flags, ...);
+int __syscall_recvmmsg(int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, ...);
+int __syscall_prlimit64(pid_t pid, int resource, intptr_t new_limit, intptr_t old_limit);
+int __syscall_sendmmsg(int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, ...);
 int __syscall_socket(int domain, int type, int protocol, int dummy1, int dummy2, int dummy3);
 int __syscall_socketpair(int domain, int type, int protocol, intptr_t fds, int dummy, int dummy2);
-int __syscall_bind(int sockfd, intptr_t addr, size_t alen, int dummy, int dummy2, int dummy3);
-int __syscall_connect(int sockfd, intptr_t addr, size_t len, int dummy, int dummy2, int dummy3);
+int __syscall_bind(int sockfd, intptr_t addr, socklen_t alen, int dummy, int dummy2, int dummy3);
+int __syscall_connect(int sockfd, intptr_t addr, socklen_t len, int dummy, int dummy2, int dummy3);
 int __syscall_listen(int sockfd, int backlog, int dummy1, int dummy2, int dummy3, int dummy4);
 int __syscall_accept4(int sockfd, intptr_t addr, intptr_t addrlen, int flags, int dummy1, int dummy2);
 int __syscall_getsockopt(int sockfd, int level, int optname, intptr_t optval, intptr_t optlen, int dummy);
-int __syscall_setsockopt(int sockfd, int level, int optname, intptr_t optval, size_t optlen, int dummy);
+int __syscall_setsockopt(int sockfd, int level, int optname, intptr_t optval, socklen_t optlen, int dummy);
 int __syscall_getsockname(int sockfd, intptr_t addr, intptr_t len, int dummy, int dummy2, int dummy3);
 int __syscall_getpeername(int sockfd, intptr_t addr, intptr_t len, int dummy, int dummy2, int dummy3);
-int __syscall_sendto(int sockfd, intptr_t msg, size_t len, int flags, intptr_t addr, size_t alen);
-int __syscall_sendmsg(int sockfd, intptr_t msg , int flags, intptr_t addr, size_t alen, int dummy);
-int __syscall_recvfrom(int sockfd, intptr_t msg, size_t len, int flags, intptr_t addr, intptr_t alen);
-int __syscall_recvmsg(int sockfd, intptr_t msg, int flags, int dummy, int dummy2, int dummy3);
+ssize_t __syscall_sendto(int sockfd, intptr_t msg, size_t len, int flags, intptr_t addr, socklen_t alen);
+ssize_t __syscall_sendmsg(int sockfd, intptr_t msg , int flags, intptr_t addr, size_t alen, int dummy);
+ssize_t __syscall_recvfrom(int sockfd, intptr_t msg, size_t len, int flags, intptr_t addr, intptr_t alen);
+ssize_t __syscall_recvmsg(int sockfd, intptr_t msg, int flags, int dummy, int dummy2, int dummy3);
 int __syscall_shutdown(int sockfd, int how, int dummy, int dummy2, int dummy3, int dummy4);
 
 #ifdef __cplusplus
diff --git a/system/lib/libc/emscripten_syscall_stubs.c b/system/lib/libc/emscripten_syscall_stubs.c
index 13ec599a8ee45..0bb85ba497e81 100644
--- a/system/lib/libc/emscripten_syscall_stubs.c
+++ b/system/lib/libc/emscripten_syscall_stubs.c
@@ -25,10 +25,10 @@
 #include <emscripten/version.h>
 #include <emscripten/stack.h>
 
-static int g_pid = 42;
-static int g_pgid = 42;
-static int g_ppid = 1;
-static int g_sid = 42;
+static pid_t g_pid = 42;
+static pid_t g_pgid = 42;
+static pid_t g_ppid = 1;
+static pid_t g_sid = 42;
 
 #ifdef NDEBUG
 #define REPORT(name)
@@ -68,7 +68,7 @@ weak int __syscall_uname(intptr_t buf) {
   return 0;
 }
 
-weak int __syscall_setpgid(int pid, int pgid) {
+weak int __syscall_setpgid(pid_t pid, pid_t pgid) {
   if (pid && pid != g_pid) {
     return -ESRCH;
   }
@@ -82,25 +82,25 @@ weak int __syscall_sync() {
   return 0;
 }
 
-weak int __syscall_getsid(int pid) {
+weak pid_t __syscall_getsid(pid_t pid) {
   if (pid && pid != g_pid) {
     return -ESRCH;
   }
   return g_sid;
 }
 
-weak int __syscall_getpgid(int pid) {
+weak pid_t __syscall_getpgid(pid_t pid) {
   if (pid && pid != g_pid) {
     return -ESRCH;
   }
   return g_pgid;
 }
 
-weak int __syscall_getpid() {
+weak pid_t __syscall_getpid() {
   return g_pid;
 }
 
-weak int __syscall_getppid() {
+weak pid_t __syscall_getppid() {
   return g_ppid;
 }
 
@@ -108,15 +108,15 @@ weak int __syscall_linkat(int olddirfd, intptr_t oldpath, int newdirfd, intptr_t
   return -EMLINK; // no hardlinks for us
 }
 
-weak int __syscall_getgroups32(int size, intptr_t list) {
-  if (size < 1) {
+weak int __syscall_getgroups32(int count, intptr_t list) {
+  if (count < 1) {
     return -EINVAL;
   }
   ((gid_t*)list)[0] = 0;
   return 1;
 }
 
-weak int __syscall_setsid() {
+weak pid_t __syscall_setsid() {
   return 0; // no-op
 }
 
@@ -137,11 +137,11 @@ weak int __syscall_getrusage(int who, intptr_t usage) {
   return 0;
 }
 
-weak int __syscall_getpriority(int which, int who) {
+weak int __syscall_getpriority(int which, id_t who) {
   return 0;
 }
 
-weak int __syscall_setpriority(int which, int who, int prio) {
+weak int __syscall_setpriority(int which, id_t who, int prio) {
   return -EPERM;
 }
 
@@ -149,19 +149,19 @@ weak int __syscall_setdomainname(intptr_t name, size_t size) {
   return -EPERM;
 }
 
-weak int __syscall_getuid32(void) {
+weak uid_t __syscall_getuid32(void) {
   return 0;
 }
 
-weak int __syscall_getgid32(void) {
+weak gid_t __syscall_getgid32(void) {
   return 0;
 }
 
-weak int __syscall_geteuid32(void) {
+weak uid_t __syscall_geteuid32(void) {
   return 0;
 }
 
-weak int __syscall_getegid32(void) {
+weak gid_t __syscall_getegid32(void) {
   return 0;
 }
 
@@ -221,7 +221,7 @@ weak int __syscall_munlockall() {
   return 0;
 }
 
-weak int __syscall_prlimit64(int pid, int resource, intptr_t new_limit, intptr_t old_limit) {
+weak int __syscall_prlimit64(pid_t pid, int resource, intptr_t new_limit, intptr_t old_limit) {
   REPORT(prlimit64);
   struct rlimit *old = (struct rlimit *)old_limit;
   if (new_limit) {
@@ -248,15 +248,19 @@ weak int __syscall_prlimit64(int pid, int resource, intptr_t new_limit, intptr_t
   return 0;
 }
 
-weak int __syscall_setsockopt(int sockfd, int level, int optname, intptr_t optval, size_t optlen, int dummy) {
+weak int __syscall_setsockopt(int sockfd, int level, int optname, intptr_t optval, socklen_t optlen, int dummy) {
   REPORT(setsockopt);
   return -ENOPROTOOPT; // The option is unknown at the level indicated.
 }
 
+weak pid_t __syscall_wait4(pid_t pid, intptr_t wstatus, int options, int rusage) {
+  REPORT(wait4);
+  return (pid_t)-1;
+}
+
 UNIMPLEMENTED(acct, (intptr_t filename))
 UNIMPLEMENTED(mincore, (intptr_t addr, size_t length, intptr_t vec))
-UNIMPLEMENTED(recvmmsg, (int sockfd, intptr_t msgvec, size_t vlen, int flags, ...))
-UNIMPLEMENTED(sendmmsg, (int sockfd, intptr_t msgvec, size_t vlen, int flags, ...))
+UNIMPLEMENTED(recvmmsg, (int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, ...))
+UNIMPLEMENTED(sendmmsg, (int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, ...))
 UNIMPLEMENTED(shutdown, (int sockfd, int how, int dummy, int dummy2, int dummy3, int dummy4))
 UNIMPLEMENTED(socketpair, (int domain, int type, int protocol, intptr_t fds, int dummy, int dummy2))
-UNIMPLEMENTED(wait4,(int pid, intptr_t wstatus, int options, int rusage))
diff --git a/system/lib/standalone/standalone.c b/system/lib/standalone/standalone.c
index c5b0b40729d9a..2576fd8665fec 100644
--- a/system/lib/standalone/standalone.c
+++ b/system/lib/standalone/standalone.c
@@ -66,11 +66,11 @@ weak int _munmap_js(
   return -ENOSYS;
 }
 
-weak int __syscall_poll(intptr_t fds, int nfds, int timeout) {
+weak int __syscall_poll(intptr_t fds, nfds_t nfds, int timeout) {
   return -ENOSYS;
 }
 
-weak int __syscall_poll_nonblocking(intptr_t fds, int nfds) {
+weak int __syscall_poll_nonblocking(intptr_t fds, nfds_t nfds) {
   return -ENOSYS;
 }
 
@@ -111,7 +111,7 @@ weak int __syscall_dup(int fd) {
   return -ENOSYS;
 }
 
-weak int __syscall_mkdirat(int dirfd, intptr_t path, int mode) {
+weak int __syscall_mkdirat(int dirfd, intptr_t path, mode_t mode) {
   return -ENOSYS;
 }
 
diff --git a/system/lib/wasmfs/js_api.cpp b/system/lib/wasmfs/js_api.cpp
index 5330b66b4074a..9b3ef3c233cdd 100644
--- a/system/lib/wasmfs/js_api.cpp
+++ b/system/lib/wasmfs/js_api.cpp
@@ -114,7 +114,7 @@ int _wasmfs_write_file(const char* pathname, const uint8_t* data, size_t data_si
   return data_size;
 }
 
-int _wasmfs_mkdir(const char* path, int mode) {
+int _wasmfs_mkdir(const char* path, mode_t mode) {
   return __syscall_mkdirat(AT_FDCWD, (intptr_t)path, mode);
 }
 
diff --git a/system/lib/wasmfs/syscalls.cpp b/system/lib/wasmfs/syscalls.cpp
index 95babec3cec1f..25978bcf9eea4 100644
--- a/system/lib/wasmfs/syscalls.cpp
+++ b/system/lib/wasmfs/syscalls.cpp
@@ -582,7 +582,7 @@ int __syscall_openat(int dirfd, intptr_t path, int flags, ...) {
   return doOpen(path::parseParent((char*)path, dirfd), flags, mode);
 }
 
-int __syscall_mknodat(int dirfd, intptr_t path, int mode, int dev) {
+int __syscall_mknodat(int dirfd, intptr_t path, mode_t mode, dev_t dev) {
   assert(dev == 0); // TODO: support special devices
   if (mode & S_IFDIR) {
     return -EINVAL;
@@ -598,7 +598,7 @@ int __syscall_mknodat(int dirfd, intptr_t path, int mode, int dev) {
 }
 
 static int
-doMkdir(path::ParsedParent parsed, int mode, backend_t backend = NullBackend) {
+doMkdir(path::ParsedParent parsed, mode_t mode, backend_t backend = NullBackend) {
   if (auto err = parsed.getError()) {
     return err;
   }
@@ -656,18 +656,18 @@ doMkdir(path::ParsedParent parsed, int mode, backend_t backend = NullBackend) {
 
 // This function is exposed to users and allows users to specify a particular
 // backend that a directory should be created within.
-int wasmfs_create_directory(char* path, int mode, backend_t backend) {
+int wasmfs_create_directory(char* path, mode_t mode, backend_t backend) {
   static_assert(std::is_same_v<decltype(doMkdir(0, 0, 0)), int>,
                 "unexpected conversion from result of doMkdir to int");
   return doMkdir(path::parseParent(path), mode, backend);
 }
 
 // TODO: Test this.
-int __syscall_mkdirat(int dirfd, intptr_t path, int mode) {
+int __syscall_mkdirat(int dirfd, intptr_t path, mode_t mode) {
   return doMkdir(path::parseParent((char*)path, dirfd), mode);
 }
 
-int __syscall_umask(int mask) {
+mode_t __syscall_umask(mode_t mask) {
   mode_t old = wasmFS.getUmask();
   wasmFS.setUmask(mask);
   return old;
@@ -1172,7 +1172,7 @@ int __syscall_utimensat(int dirFD, intptr_t path_, intptr_t times_, int flags) {
 }
 
 // TODO: Test this with non-AT_FDCWD values.
-int __syscall_fchmodat2(int dirfd, intptr_t path, int mode, int flags) {
+int __syscall_fchmodat2(int dirfd, intptr_t path, mode_t mode, int flags) {
   if (flags & ~AT_SYMLINK_NOFOLLOW) {
     // TODO: Test this case.
     return -EINVAL;
@@ -1188,11 +1188,11 @@ int __syscall_fchmodat2(int dirfd, intptr_t path, int mode, int flags) {
   return 0;
 }
 
-int __syscall_chmod(intptr_t path, int mode) {
+int __syscall_chmod(intptr_t path, mode_t mode) {
   return __syscall_fchmodat2(AT_FDCWD, path, mode, 0);
 }
 
-int __syscall_fchmod(int fd, int mode) {
+int __syscall_fchmod(int fd, mode_t mode) {
   auto openFile = wasmFS.getFileTable().locked().getEntry(fd);
   if (!openFile) {
     return -EBADF;
@@ -1204,7 +1204,7 @@ int __syscall_fchmod(int fd, int mode) {
 }
 
 int __syscall_fchownat(
-  int dirfd, intptr_t path, int owner, int group, int flags) {
+  int dirfd, intptr_t path, uid_t owner, gid_t group, int flags) {
   // Only accept valid flags.
   if (flags & ~(AT_EMPTY_PATH | AT_SYMLINK_NOFOLLOW)) {
     // TODO: Test this case.
@@ -1220,7 +1220,7 @@ int __syscall_fchownat(
   return 0;
 }
 
-int __syscall_fchown32(int fd, int owner, int group) {
+int __syscall_fchown32(int fd, uid_t owner, gid_t group) {
   return __syscall_fchownat(fd, (intptr_t) "", owner, group, AT_EMPTY_PATH);
 }
 
@@ -1385,7 +1385,7 @@ int __syscall_pipe2(intptr_t fd, int flags) {
 }
 
 // int poll(struct pollfd* fds, nfds_t nfds, int timeout);
-int __syscall_poll(intptr_t fds_, int nfds, int timeout) {
+int __syscall_poll(intptr_t fds_, nfds_t nfds, int timeout) {
   struct pollfd* fds = (struct pollfd*)fds_;
   auto fileTable = wasmFS.getFileTable().locked();
 
@@ -1438,7 +1438,7 @@ int __syscall_poll(intptr_t fds_, int nfds, int timeout) {
 
 // libc routes zero-timeout poll() calls here (see musl's poll.c). WasmFS's
 // __syscall_poll never blocks, so the zero-timeout probe is the same call.
-int __syscall_poll_nonblocking(intptr_t fds, int nfds) {
+int __syscall_poll_nonblocking(intptr_t fds, nfds_t nfds) {
   return __syscall_poll(fds, nfds, 0);
 }
 
@@ -1731,12 +1731,12 @@ int __syscall_accept4(int sockfd,
 }
 
 int __syscall_bind(
-  int sockfd, intptr_t addr, size_t alen, int dummy, int dummy2, int dummy3) {
+  int sockfd, intptr_t addr, socklen_t alen, int dummy, int dummy2, int dummy3) {
   return -ENOSYS;
 }
 
 int __syscall_connect(
-  int sockfd, intptr_t addr, size_t len, int dummy, int dummy2, int dummy3) {
+  int sockfd, intptr_t addr, socklen_t len, int dummy, int dummy2, int dummy3) {
   return -ENOSYS;
 }
 
@@ -1769,26 +1769,26 @@ int __syscall_getpeername(
   return -ENOSYS;
 }
 
-int __syscall_sendto(
-  int sockfd, intptr_t msg, size_t len, int flags, intptr_t addr, size_t alen) {
+ssize_t __syscall_sendto(
+  int sockfd, intptr_t msg, size_t len, int flags, intptr_t addr, socklen_t alen) {
   return -ENOSYS;
 }
 
-int __syscall_sendmsg(
+ssize_t __syscall_sendmsg(
   int sockfd, intptr_t msg, int flags, intptr_t addr, size_t alen, int dummy) {
   return -ENOSYS;
 }
 
-int __syscall_recvfrom(int sockfd,
-                       intptr_t msg,
-                       size_t len,
-                       int flags,
-                       intptr_t addr,
-                       intptr_t alen) {
+ssize_t __syscall_recvfrom(int sockfd,
+                           intptr_t msg,
+                           size_t len,
+                           int flags,
+                           intptr_t addr,
+                           intptr_t alen) {
   return -ENOSYS;
 }
 
-int __syscall_recvmsg(
+ssize_t __syscall_recvmsg(
   int sockfd, intptr_t msg, int flags, int dummy, int dummy2, int dummy3) {
   return -ENOSYS;
 }
diff --git a/test/codesize/test_codesize_hello_dylink_all.json b/test/codesize/test_codesize_hello_dylink_all.json
index 584a099573a66..fde777a4819d0 100644
--- a/test/codesize/test_codesize_hello_dylink_all.json
+++ b/test/codesize/test_codesize_hello_dylink_all.json
@@ -1,7 +1,7 @@
 {
   "a.out.js": 268274,
-  "a.out.nodebug.wasm": 587640,
-  "total": 855914,
+  "a.out.nodebug.wasm": 587670,
+  "total": 855944,
   "sent": [
     "IMG_Init",
     "IMG_Load",
@@ -5324,9 +5324,11 @@
     "$vwarnx",
     "$vwprintf",
     "$vwscanf",
+    "$wait",
     "$wait3",
     "$wait4",
     "$waitid",
+    "$waitpid",
     "$walk",
     "$warn",
     "$warnx",