From fb370451e736c934bbc7644da114c796afb1b735 Mon Sep 17 00:00:00 2001
From: John Denker <jsd@av8n.com>
Date: Sun, 15 Jul 2012 02:35:13 -0700
Subject: probably working

---
 tools/hi-q.c | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/tools/hi-q.c b/tools/hi-q.c
index b2a4c7c..f2da44d 100644
--- a/tools/hi-q.c
+++ b/tools/hi-q.c
@@ -212,7 +212,9 @@ int main(int argc, char** argv, char const * const * env) {
   const int rEnd(0);  // end of a pipe for reading
   const int wEnd(1);  // end of a pipe for writing
   int sync[2];
+  int resync[2];
   if (pipe(sync) != 0) cerr << "sync pipe failed" << endl;
+  if (pipe(resync) != 0) cerr << "resync pipe failed" << endl;
 
 // At this point, there are some loop invariants;
 // (a) fd0 is open (standard input) and has the email msg, 
@@ -272,6 +274,7 @@ int main(int argc, char** argv, char const * const * env) {
         cerr << "*** kid " << ii << " setpgid OK" << endl;
       }
 
+// everybody else has to wait for us to get this far
       if (ii == 0) {
         int junk(1);
         write(sync[wEnd], &junk, 1);
@@ -283,7 +286,22 @@ int main(int argc, char** argv, char const * const * env) {
         << "  pgid: " << getpgid(0)
         << " starts" << endl;
 #endif
-      usleep(50000);
+      close(resync[wEnd]);
+// Now we wait for everybody else:
+      if (ii==0) {
+        int junk;
+        cerr << "about to read resync" << endl;
+        ssize_t rslt = read(resync[rEnd], &junk, 1);
+        if (rslt != 1) {
+          cerr << "bad sync ... 1 != " << rslt << endl;
+        } else {
+          cerr << "back from read resync, good: " << rslt << endl;
+        }
+      }
+
+//######      usleep(50000);
+
+
 // Now that we are through creating pipes, we don't
 // need to continue blocking fd1:
       close(1);
@@ -324,18 +342,18 @@ int main(int argc, char** argv, char const * const * env) {
     }
     close(kid_end);
 
+// Let kid #0 run a little ways:
       if (ii==0) {
         int junk;
         cerr << "about to read sync" << endl;
         ssize_t rslt = read(sync[rEnd], &junk, 1);
-        if (rslt != 1) {
+        if (rslt < 0) {
           cerr << "bad sync ... 1 != " << rslt << endl;
         } else {
           cerr << "back from read sync, good: " << rslt << endl;
         }
       }
 
-
 // it is important to let kid#0 run a while;
 // otherwise it won't fully exist when the other kids start,
 // and depending race conditions, the setpgid could fail
@@ -351,6 +369,8 @@ int main(int argc, char** argv, char const * const * env) {
 
 // here with the whole pipeline of kids launched
 
+      close(resync[wEnd]);
+
   close(0);             // the reading end of stdin was
                         // delegated to the first child
 
-- 
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