socket: TCP_CORK, TCP_NODELAY

* libguile/socket.c (scm_init_socket): Define TCP_NODELAY and TCP_CORK
  if they are available.
* doc/ref/posix.texi (Network Sockets and Communication): Add
  documentation.
* NEWS: Add entry.

NEWS

@@ -54,6 +54,9 @@ avoid the crashes that led to the introduction of locking, but without
 locks.  For that reason we have removed port locks, and removed the
 "_unlocked" port API variants that were introduced in 2.1.0.
 
+* New interfaces
+** `TCP_NODELAY' and `TCP_CORK' socket options, if provided by the system
+
 * New deprecations
 ** `_IONBF', `_IOLBF', and `_IOFBF'
 

doc/ref/posix.texi

@@ -3178,6 +3178,15 @@ supporting that.
 @end defvar
 @end deffn
 
+For @code{IPPROTO_TCP} level the following @var{optname}s are defined
+(when provided by the system).  For their meaning see @command{man 7
+tcp}.
+
+@defvar TCP_NODELAY
+@defvarx TCP_CORK
+The @var{value} taken or returned is an integer.
+@end defvar
+
 @deffn {Scheme Procedure} shutdown sock how
 @deffnx {C Function} scm_shutdown (sock, how)
 Sockets can be closed simply by using @code{close-port}.  The

libguile/socket.c

@@ -40,6 +40,7 @@
 #include <sys/un.h>
 #endif
 #include <netinet/in.h>
+#include <netinet/tcp.h>
 #include <netdb.h>
 #include <arpa/inet.h>
 
@@ -1713,6 +1714,14 @@ scm_init_socket ()
   scm_c_define ("MSG_DONTROUTE", scm_from_int (MSG_DONTROUTE));
 #endif
 
+  /* TCP options.  */
+#ifdef TCP_NODELAY
+  scm_c_define ("TCP_NODELAY", scm_from_int (TCP_NODELAY));
+#endif
+#ifdef TCP_CORK
+  scm_c_define ("TCP_CORK", scm_from_int (TCP_CORK));
+#endif
+
 #ifdef IP_ADD_MEMBERSHIP
   scm_c_define ("IP_ADD_MEMBERSHIP", scm_from_int (IP_ADD_MEMBERSHIP));
   scm_c_define ("IP_DROP_MEMBERSHIP", scm_from_int (IP_DROP_MEMBERSHIP));