diff --git a/libc/include/sys/mman.h b/libc/include/sys/mman.h
index 1440dc6..1e752c4 100644
--- a/libc/include/sys/mman.h
+++ b/libc/include/sys/mman.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_MMAN_H_
 #define _SYS_MMAN_H_
 
@@ -44,27 +45,27 @@
 #define MREMAP_FIXED    2
 
 #if defined(__USE_FILE_OFFSET64)
-void* mmap(void*, size_t, int, int, int, off_t) __RENAME(mmap64) __INTRODUCED_IN(21);
+void* mmap(void* __addr, size_t __size, int __prot, int __flags, int __fd, off_t __offset) __RENAME(mmap64) __INTRODUCED_IN(21);
 #else
-void* mmap(void*, size_t, int, int, int, off_t);
+void* mmap(void* __addr, size_t __size, int __prot, int __flags, int __fd, off_t __offset);
 #endif
 
-void* mmap64(void*, size_t, int, int, int, off64_t) __INTRODUCED_IN(21);
+void* mmap64(void* __addr, size_t __size, int __prot, int __flags, int __fd, off64_t __offset) __INTRODUCED_IN(21);
 
-int munmap(void*, size_t);
-int msync(void*, size_t, int);
-int mprotect(void*, size_t, int);
-void* mremap(void*, size_t, size_t, int, ...);
+int munmap(void* __addr, size_t __size);
+int msync(void* __addr, size_t __size, int __flags);
+int mprotect(void* __addr, size_t __size, int __prot);
+void* mremap(void* __old_addr, size_t __old_size, size_t __new_size, int __flags, ...);
 
-int mlockall(int) __INTRODUCED_IN(17);
+int mlockall(int __flags) __INTRODUCED_IN(17);
 int munlockall(void) __INTRODUCED_IN(17);
 
-int mlock(const void*, size_t);
-int munlock(const void*, size_t);
+int mlock(const void* __addr, size_t __size);
+int munlock(const void* __addr, size_t __size);
 
-int mincore(void*, size_t, unsigned char*);
+int mincore(void* __addr, size_t __size, unsigned char* __vector);
 
-int madvise(void*, size_t, int);
+int madvise(void* __addr, size_t __size, int __advice);
 
 #if __ANDROID_API__ >= __ANDROID_API_M__
 /*
@@ -81,8 +82,8 @@
 #define POSIX_MADV_WILLNEED   MADV_WILLNEED
 #define POSIX_MADV_DONTNEED   MADV_DONTNEED
 #endif
-int posix_madvise(void*, size_t, int) __INTRODUCED_IN(23);
+int posix_madvise(void* __addr, size_t __size, int __advice) __INTRODUCED_IN(23);
 
 __END_DECLS
 
-#endif /* _SYS_MMAN_H_ */
+#endif