diff --git a/libc/bionic/sysconf.cpp b/libc/bionic/sysconf.cpp
index 8309f08..7734e40 100644
--- a/libc/bionic/sysconf.cpp
+++ b/libc/bionic/sysconf.cpp
@@ -150,7 +150,7 @@
   return (rc == -1) ? -1 : _POSIX_VERSION;
 }
 
-int sysconf(int name) {
+long sysconf(int name) {
     switch (name) {
 #ifdef _POSIX_ARG_MAX
     case _SC_ARG_MAX:           return _POSIX_ARG_MAX;
diff --git a/libc/include/sys/sysconf.h b/libc/include/sys/sysconf.h
index 0a46e7a..3d058d7 100644
--- a/libc/include/sys/sysconf.h
+++ b/libc/include/sys/sysconf.h
@@ -129,7 +129,7 @@
 #define _SC_AVPHYS_PAGES                0x0063
 #define _SC_MONOTONIC_CLOCK             0x0064
 
-extern int sysconf(int name);
+long sysconf(int);
 
 __END_DECLS
 
diff --git a/libc/include/unistd.h b/libc/include/unistd.h
index 9b9adce..1bfdb0e 100644
--- a/libc/include/unistd.h
+++ b/libc/include/unistd.h
@@ -177,7 +177,7 @@
 
 int getpagesize(void);
 
-extern int sysconf(int  name);
+long sysconf(int);
 
 extern int daemon(int, int);