a very simple fix - if I'd only thought if it last week :)

rsh relies on stdin being blocking
ssh relies on stdout being non-blocking

what we've done before is to set both stdin and stdout to either
blocking or non-blocking. Now I set stdin to blocking and stdout to
non-blocking. This seems to fix all cases I've tested.

diff --git a/util.c b/util.c
index 03a626e..7c589b3 100644 (file)
--- a/util.c
+++ b/util.c
@@ -28,10 +28,7 @@ extern int verbose;
 
 
 /****************************************************************************
-Set a fd into nonblocking mode. Uses POSIX O_NONBLOCK if available,
-else
-if SYSV use O_NDELAY
-if BSD use FNDELAY
+Set a fd into nonblocking mode
 ****************************************************************************/
 void set_nonblocking(int fd)
 {
@@ -45,6 +42,21 @@ void set_nonblocking(int fd)
        }
 }
 
+/****************************************************************************
+Set a fd into blocking mode
+****************************************************************************/
+void set_blocking(int fd)
+{
+       int val;
+
+       if((val = fcntl(fd, F_GETFL, 0)) == -1)
+               return;
+       if (val & NONBLOCK_FLAG) {
+               val &= ~NONBLOCK_FLAG;
+               fcntl(fd, F_SETFL, val);
+       }
+}
+
 
 /* create a file descriptor pair - like pipe() but use socketpair if
    possible (because of blocking issues on pipes)
@@ -70,7 +82,7 @@ int fd_pair(int fd[2])
 }
 
 
-/* this is taken from CVS */
+/* this is derived from CVS code */
 int piped_child(char **command,int *f_in,int *f_out)
 {
   int pid;
@@ -103,6 +115,7 @@ int piped_child(char **command,int *f_in,int *f_out)
       if (to_child_pipe[0] != STDIN_FILENO) close(to_child_pipe[0]);
       if (from_child_pipe[1] != STDOUT_FILENO) close(from_child_pipe[1]);
       umask(orig_umask);
+      set_blocking(STDIN_FILENO);
       execvp(command[0], command);
       rprintf(FERROR,"Failed to exec %s : %s\n",
              command[0],strerror(errno));