If the timeout is not set, don't send a zeroed timeout to select.

This solves the problem with nc hogging all cpu.

1 files changed, 8 insertions, 2 deletions

diff --git a/src/usr.bin/nc/netcat.c b/src/usr.bin/nc/netcat.c
index 31f49a3fc3..eb4351dbe1 100644
--- a/src/usr.bin/nc/netcat.c
+++ b/src/usr.bin/nc/netcat.c
@@ -1125,14 +1125,20 @@ readwrite(fd)
 
 /* and now the big ol' select shoveling loop ... */
         while (FD_ISSET(fd, &fds1)) {   /* i.e. till the *net* closes! */
+                struct timeval *tv;
+
                 wretry = 8200;  /* more than we'll ever hafta write */
                 if (wfirst) {   /* any saved stdin buffer? */
                         wfirst = 0;     /* clear flag for the duration */
                         goto shovel;    /* and go handle it first */
                 }
                 fds2 = fds1;
-                memcpy(&timer2, &timer1, sizeof(struct timeval));
-                rr = select(getdtablesize(), &fds2, 0, 0, &timer2);
+                if (timer1.tv_sec > 0 || timer1.tv_usec > 0) {
+                        memcpy(&timer2, &timer1, sizeof(struct timeval));
+                        tv = &timer2;
+                } else
+                        tv = NULL;
+                rr = select(getdtablesize(), &fds2, 0, 0, tv);
                 if (rr < 0) {
                         if (errno != EINTR) {   /* might have gotten ^Zed, etc
                                                  * ? */