1 files changed, 53 insertions, 0 deletions
diff --git a/libraries/base/cbits/inputReady.c b/libraries/base/cbits/inputReady.c
new file mode 100644
index 0000000000..4cb9908617
--- /dev/null
+++ b/libraries/base/cbits/inputReady.c
@@ -0,0 +1,53 @@
+/* 
+ * (c) The GRASP/AQUA Project, Glasgow University, 1994-1998
+ *
+ * $Id: inputReady.c,v 1.1 2001/06/28 14:15:04 simonmar Exp $
+ *
+ * hReady Runtime Support
+ */
+
+/* select and supporting types is not */
+#ifndef _AIX
+#define NON_POSIX_SOURCE  
+#endif
+
+#include "HsCore.h"
+
+/*
+ * inputReady(fd) checks to see whether input is available on the file
+ * descriptor 'fd'.  Input meaning 'can I safely read at least a
+ * *character* from this file object without blocking?'
+ */
+int
+inputReady(int fd, int msecs)
+{
+    int maxfd, ready;
+#ifndef mingw32_TARGET_OS
+    fd_set rfd;
+    struct timeval tv;
+#endif
+
+#ifdef mingw32_TARGET_OS
+    return 1;
+#else
+    FD_ZERO(&rfd);
+    FD_SET(fd, &rfd);
+
+    /* select() will consider the descriptor set in the range of 0 to
+     * (maxfd-1) 
+     */
+    maxfd = fd + 1;
+    tv.tv_sec  = msecs / 1000;
+    tv.tv_usec = msecs % 1000;
+
+    while ((ready = select(maxfd, &rfd, NULL, NULL, &tv)) < 0 ) {
+      if (errno != EINTR ) {
+          return -1;
+      }
+   }
+
+    /* 1 => Input ready, 0 => not ready, -1 => error */
+    return (ready);
+
+#endif
+}