fix signal race (Scott Lamb)

CHANGES

@@ -3,6 +3,7 @@
   add io_passfd and io_receivefd (and test/fdpassing.c)
   io_trywrite and io_waitwrite not ignore SIGPIPE
   add man pages for libio, safemult
+  fix possible signal race in io_tryread and io_trywrite (Scott Lamb)
 
 0.18:
   make libowfat compile on BSD again (sorry, and thanks to everyone who

io/io_tryread.c

@@ -21,7 +21,7 @@ int64 io_tryread(int64 d,char* buf,int64 len) {
 	    e->next_read=-1;
 	    return -1;
     }
-    new.it_interval.tv_usec=0;
+    new.it_interval.tv_usec=10000;
     new.it_interval.tv_sec=0;
     new.it_value.tv_usec=10000;
     new.it_value.tv_sec=0;

io/io_trywrite.c

@@ -22,7 +22,7 @@ int64 io_trywrite(int64 d,const char* buf,int64 len) {
 	    e->next_write=-1;
 	    return -1;
     }
-    new.it_interval.tv_usec=0;
+    new.it_interval.tv_usec=10000;
     new.it_interval.tv_sec=0;
     new.it_value.tv_usec=10000;
     new.it_value.tv_sec=0;