2005-02-15 Andrew J. Schorr <ajschorr@alumni.princeton.edu>

	* network.h: Declare new function set_nonblocking.  Indicate that
	  readn and writen are deprecated.
	* network.c: (set_nonblocking) New function to make a file descriptor
	  non-blocking, since it seems silly to have fcntl calls sprinkled
	  throughout the code.
diff --git a/lib/ChangeLog b/lib/ChangeLog
index 2b29056..ee02438 100644
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,3 +1,11 @@
+2005-02-15 Andrew J. Schorr <ajschorr@alumni.princeton.edu>
+	
+	* network.h: Declare new function set_nonblocking.  Indicate that
+	  readn and writen are deprecated.
+	* network.c: (set_nonblocking) New function to make a file descriptor
+	  non-blocking, since it seems silly to have fcntl calls sprinkled
+	  throughout the code.
+
 2005-02-14 Paul Jakma <paul.jakma@sun.com>
 
 	* stream.h: Unsigned long updated to size_t
diff --git a/lib/network.c b/lib/network.c
index e1f733c..3b29672 100644
--- a/lib/network.c
+++ b/lib/network.c
@@ -21,6 +21,8 @@
  */
 
 #include <zebra.h>
+#include "log.h"
+#include "network.h"
 
 /* Read nbytes from fd and store into ptr. */
 int
@@ -69,3 +71,15 @@
     }
   return nbytes - nleft;
 }
+
+int
+set_nonblocking(int fd)
+{
+  if (fcntl(fd, F_SETFL, (fcntl(fd, F_GETFL) | O_NONBLOCK)) < 0)
+    {
+      zlog_warn("fcntl failed setting fd %d non-blocking: %s",
+      		fd, safe_strerror(errno));
+      return -1;
+    }
+  return 0;
+}
diff --git a/lib/network.h b/lib/network.h
index f0a7d4d..589b80e 100644
--- a/lib/network.h
+++ b/lib/network.h
@@ -23,7 +23,14 @@
 #ifndef _ZEBRA_NETWORK_H
 #define _ZEBRA_NETWORK_H
 
+/* Both readn and writen are deprecated and will be removed.  They are not
+   suitable for use with non-blocking file descriptors.
+ */
 int readn (int, u_char *, int);
 int writen (int, const u_char *, int);
 
+/* Set the file descriptor to use non-blocking I/O.  Returns 0 for success,
+   -1 on error. */
+extern int set_nonblocking(int fd);
+
 #endif /* _ZEBRA_NETWORK_H */