diff --git a/libc/bionic/semaphore.c b/libc/bionic/semaphore.c
index 0c94600..f4eebce 100644
--- a/libc/bionic/semaphore.c
+++ b/libc/bionic/semaphore.c
@@ -196,7 +196,8 @@
     if (__atomic_dec_if_positive(&sem->count) > 0) {
         return 0;
     } else {
-        return EAGAIN;
+        errno = EAGAIN;
+        return -1;
     }
 }
 
diff --git a/libc/docs/CHANGES.TXT b/libc/docs/CHANGES.TXT
index c2655c5..7c8f38c 100644
--- a/libc/docs/CHANGES.TXT
+++ b/libc/docs/CHANGES.TXT
@@ -46,7 +46,14 @@
 
 - <wchar.h>: Add mbstowcs() and wcstombs()
 
-- add clone() implementation for ARM (x86 and SH-4 not working yet)
+- add clone() implementation for ARM (x86 and SH-4 not working yet).
+
+- <sys/epoll.h>: <sys/system_properties.h>: Add missing C++ inclusion guards
+
+- fix getpwnam() and getpwgrp() to accept "app_0" as a valid user name.
+
+- fix sem_trywait() to return -1 and set errno to EAGAIN, instead of
+  returning EAGAIN directly.
 
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 Differences between Android 2.1 and 2.0.1: