https://github.com/termux/termux-packages/issues/15852

--- a/environ.c
+++ b/environ.c
@@ -12,6 +12,8 @@
 #include <conio.h>
 #include <io.h>
 #include <process.h>
+#else
+#include <sys/wait.h>
 #endif
 
 #include <fcntl.h>