diff --git a/userspace/libraries/LibC/netdb.cpp b/userspace/libraries/LibC/netdb.cpp
index a0a1d8db..6217dce7 100644
--- a/userspace/libraries/LibC/netdb.cpp
+++ b/userspace/libraries/LibC/netdb.cpp
@@ -319,3 +319,9 @@ struct servent* getservbyname(const char* name, const char* proto)
 	dwarnln("TODO: getservbyname(\"{}\", \"{}\")", name, proto);
 	return nullptr;
 }
+
+struct protoent* getprotobynumber(int proto)
+{
+	dwarnln("TODO: getprotobynumber({})", proto);
+	return nullptr;
+}
diff --git a/userspace/libraries/LibC/stdio.cpp b/userspace/libraries/LibC/stdio.cpp
index 95c1472e..1b6c6dad 100644
--- a/userspace/libraries/LibC/stdio.cpp
+++ b/userspace/libraries/LibC/stdio.cpp
@@ -649,6 +649,13 @@ char* gets(char* buffer)
 	}
 }
 
+FILE* open_memstream(char** bufp, size_t* sizep)
+{
+	(void)bufp;
+	(void)sizep;
+	ASSERT_NOT_REACHED();
+}
+
 int pclose(FILE* file)
 {
 	if (file->pid == -1)
diff --git a/userspace/libraries/LibC/sys/mman.cpp b/userspace/libraries/LibC/sys/mman.cpp
index ebc4b3c7..09f11bf5 100644
--- a/userspace/libraries/LibC/sys/mman.cpp
+++ b/userspace/libraries/LibC/sys/mman.cpp
@@ -53,6 +53,11 @@ int mlock(const void*, size_t)
 	ASSERT_NOT_REACHED();
 }
 
+int munlock(const void*, size_t)
+{
+	ASSERT_NOT_REACHED();
+}
+
 int shm_open(const char* name, int oflag, mode_t mode)
 {
 	(void)name;
diff --git a/userspace/libraries/LibC/unistd.cpp b/userspace/libraries/LibC/unistd.cpp
index 7209a0ca..1ea5f819 100644
--- a/userspace/libraries/LibC/unistd.cpp
+++ b/userspace/libraries/LibC/unistd.cpp
@@ -689,6 +689,30 @@ int getpagesize(void)
 	return PAGE_SIZE;
 }
 
+int lockf(int fildes, int function, off_t size)
+{
+	(void)fildes;
+	(void)function;
+	(void)size;
+	derrorln("TODO: lockf");
+	ASSERT_NOT_REACHED();
+}
+
+int nice(int incr)
+{
+	dwarnln("TODO: nice({})", incr);
+	errno = EPERM;
+	return -1;
+}
+
+char* crypt(const char* key, const char* salt)
+{
+	(void)key;
+	(void)salt;
+	derrorln("TODO: crypt");
+	ASSERT_NOT_REACHED();
+}
+
 char* getpass(const char* prompt)
 {
 	static char buffer[PASS_MAX];
@@ -774,6 +798,12 @@ pid_t getpgid(pid_t pid)
 	return syscall(SYS_GET_PGID, pid);
 }
 
+pid_t getsid(pid_t pid)
+{
+	(void)pid;
+	ASSERT_NOT_REACHED();
+}
+
 int tcgetpgrp(int fildes)
 {
 	return syscall(SYS_TCGETPGRP, fildes);
diff --git a/userspace/libraries/LibC/wchar.cpp b/userspace/libraries/LibC/wchar.cpp
index 299fe79d..a1f8ef44 100644
--- a/userspace/libraries/LibC/wchar.cpp
+++ b/userspace/libraries/LibC/wchar.cpp
@@ -26,6 +26,7 @@ int wcwidth(wchar_t wc)
 
 wchar_t* wcstok(wchar_t* __restrict, const wchar_t* __restrict, wchar_t** __restrict) { ASSERT_NOT_REACHED(); }
 long wcstol(const wchar_t* __restrict, wchar_t** __restrict, int) { ASSERT_NOT_REACHED(); }
+unsigned long wcstoul(const wchar_t* __restrict, wchar_t** __restrict, int) { ASSERT_NOT_REACHED(); }
 int swprintf(wchar_t* __restrict, size_t, const wchar_t* __restrict, ...) { ASSERT_NOT_REACHED(); }
 
 size_t wcrtomb(char* __restrict s, wchar_t ws, mbstate_t* __restrict ps)