fix: use send instead of write to prevent SIGPIPE

src/loop/lnm_loop_io.c

@@ -1,6 +1,7 @@
 #include <errno.h>
 #include <string.h>
 #include <unistd.h>
+#include <sys/socket.h>
 
 #include "lnm/loop.h"
 #include "lnm/loop_internal.h"
@@ -43,7 +44,9 @@ void lnm_loop_conn_io_res(lnm_loop *l, lnm_loop_conn *conn) {
     ssize_t res;
 
     do {
-      res = write(conn->fd, conn->w.buf, conn->w.size);
+      // Send with MSG_NOSIGNAL prevents closed pipes from exiting the program
+      // with SIGPIPE
+      res = send(conn->fd, conn->w.buf, conn->w.size, MSG_NOSIGNAL);
     } while (res < 0 && errno == EINTR);
 
     // Write can't be performed without blocking; we come back later