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diff --git a/.gitignore b/.gitignore
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+++ b/.gitignore
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+*.so
diff --git a/COPYING b/COPYING
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index 0000000..cca7fc2
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,165 @@
+                   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
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+  You may convey a covered work under sections 3 and 4 of this License
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+   Library is used in it and that the Library and its use are
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diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..07e870d
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,33 @@
+prefix = $(HOME)
+libdir = $(prefix)/lib
+INSTALL = install
+CC = gcc
+CFLAGS = -O2 -Wall -g
+
+all: libnodelay.so
+libnodelay.so: nodelay.c
+        $(CC) $(CFLAGS) -fPIC -Wall -W -o $@ -shared -ldl $<
+clean:
+        $(RM) $(shell cat .gitignore)
+install: libnodelay.so
+        $(INSTALL) -m 755 -d $(DESTDIR)$(libdir)
+        $(INSTALL) -m 644 $< $(DESTDIR)$(libdir)
+
+test: libnodelay.so
+        test -n "$(TEST_PORT)" || { echo TEST_PORT not set; exit 1; }
+        if [ -e test-server.pid ]; then echo test-server.pid exists; exit 1; fi
+        if [ -e test-client.pid ]; then echo test-client.pid exists; exit 1; fi
+        LD_PRELOAD=$(CURDIR)/$< \
+                strace -o test-server.out \
+                                nc -l $(TEST_PORT) & \
+                echo $$! > test-server.pid
+        LD_PRELOAD=$(CURDIR)/$< \
+                strace -o test-client.out \
+                                nc -q 1 127.0.0.1 $(TEST_PORT) & \
+                echo $$! > test-client.pid
+        kill `cat test-client.pid` || sleep 1
+        kill `cat test-server.pid` || sleep 1
+        $(RM) test-server.pid test-client.pid
+        grep setsockopt.*TCP_NODELAY test-server.out
+        grep setsockopt.*TCP_NODELAY test-client.out
+        $(RM) test-server.out test-client.out
diff --git a/README b/README
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--- /dev/null
+++ b/README
@@ -0,0 +1,24 @@
+libnodelay - LD_PRELOAD library to disable Nagle's algorithm
+============================================================
+
+If you're tired of digging through a mess of code and confusing/obscure
+configuration options, you should LD_PRELOAD this library instead.
+
+Disabling Nagle's algorithm can result in a performance improvement
+for latency-sensitive applications that use TCP.
+
+More about Nagle's algorithm is here:
+
+  http://en.wikipedia.org/wiki/Nagle%27s_algorithm
+
+Home directory Installation
+---------------------------
+
+        $ make
+        $ make install
+
+System-wide Installation
+------------------------
+
+        $ make
+        # make install prefix=/usr
diff --git a/nodelay.c b/nodelay.c
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index 0000000..134a95a
--- /dev/null
+++ b/nodelay.c
@@ -0,0 +1,55 @@
+/*
+ * LD_PRELOAD-able library that disables the Nagle algorithm for all
+ * TCP sockets, both server and client.
+ *
+ * Copyright (C) 2009 Eric Wong <normalperson@yhbt.net>
+ *
+ * Licensed under the Lesser GNU General Public License, version 3.
+ */
+#define _GNU_SOURCE
+#include <dlfcn.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <errno.h>
+#include <unistd.h>
+
+#if defined(__GNUC__) && (__GNUC__ >= 3)
+#  define unlikely(x)        __builtin_expect (!!(x), 0)
+# else
+#  define unlikely(x)        (x)
+#endif
+
+static int (*real_socket)(int, int, int);
+
+void __attribute__ ((constructor)) nodelay_init(void)
+{
+        real_socket = dlsym(RTLD_NEXT, "socket");
+
+        if (!real_socket || dlerror())
+                _exit(1);
+}
+
+int socket(int domain, int type, int protocol)
+{
+        int fd;
+
+        if (unlikely(!real_socket))
+                nodelay_init();
+
+        fd = real_socket(domain, type, protocol);
+
+        if (fd >= 0 &&
+            protocol == IPPROTO_TCP &&
+            type == SOCK_STREAM &&
+            domain == PF_INET) {
+                int orig_errno = errno;
+                int optval = 1;
+
+                /* don't care too much if it fails */
+                setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &optval, sizeof(int));
+                errno = orig_errno;
+        }
+
+        return fd;
+}