diff --git a/libc/SYSCALLS.TXT b/libc/SYSCALLS.TXT
index 42c8f01..fd302f9 100644
--- a/libc/SYSCALLS.TXT
+++ b/libc/SYSCALLS.TXT
@@ -117,8 +117,8 @@
 int         munlockall()   all
 int         mincore(void*  start, size_t  length, unsigned char*  vec)   all
 int         __ioctl:ioctl(int, int, void*)  all
-int         readv(int, const struct iovec*, int)   all
-int         writev(int, const struct iovec*, int)  all
+ssize_t     readv(int, const struct iovec*, int)   all
+ssize_t     writev(int, const struct iovec*, int)  all
 int         __fcntl64:fcntl64(int, int, void*)  arm,mips,x86
 int         fcntl(int, int, void*)  arm64,mips64,x86_64
 int         flock(int, int)   all
diff --git a/libc/include/sys/uio.h b/libc/include/sys/uio.h
index 7a009b4..0e56d7d 100644
--- a/libc/include/sys/uio.h
+++ b/libc/include/sys/uio.h
@@ -34,8 +34,8 @@
 
 __BEGIN_DECLS
 
-int readv(int, const struct iovec*, int);
-int writev(int, const struct iovec*, int);
+ssize_t readv(int, const struct iovec*, int);
+ssize_t writev(int, const struct iovec*, int);
 
 #if defined(__USE_GNU)
 #if defined(__USE_FILE_OFFSET64)