Make the pager work.

pager.c

@@ -1,19 +1,26 @@
 #include "cache.h"
+#include "spawn-pipe.h"
 
 /*
  * This is split up from the rest of git so that we might do
  * something different on Windows, for example.
  */
 
+#ifndef __MINGW32__
 static void run_pager(const char *pager)
 {
 	execlp(pager, pager, NULL);
 	execl("/bin/sh", "sh", "-c", pager, NULL);
 }
+#endif
 
 void setup_pager(void)
 {
+#ifndef __MINGW32__
 	pid_t pid;
+#else
+	const char *pager_argv[] = { "sh", "-c", NULL, NULL };
+#endif
 	int fd[2];
 	const char *pager = getenv("GIT_PAGER");
 
@@ -30,6 +37,7 @@ void setup_pager(void)
 
 	if (pipe(fd) < 0)
 		return;
+#ifndef __MINGW32__
 	pid = fork();
 	if (pid < 0) {
 		close(fd[0]);
@@ -54,4 +62,14 @@ void setup_pager(void)
 	run_pager(pager);
 	die("unable to execute pager '%s'", pager);
 	exit(255);
+#else
+	/* spawn the pager */
+	pager_argv[2] = pager;
+	if (spawnvpe_pipe(pager_argv[0], pager_argv, environ, fd, NULL) < 0)
+		return;
+
+	/* original process continues, but writes to the pipe */
+	dup2(fd[1], 1);
+	close(fd[1]);
+#endif
 }