Increase size of test io-29.34 so that it more portably tests the case where

the OS networking machinery gets backed up and blocks.
Added several TODO comments on potential simplifications.

2 files changed, 11 insertions, 2 deletions

diff --git a/generic/tclIO.c b/generic/tclIO.c
index 4e325ba..9e0d7f1 100644
--- a/generic/tclIO.c
+++ b/generic/tclIO.c
@@ -2555,6 +2555,7 @@ FlushChannel(
 	PreserveChannelBuffer(bufPtr);
 	toWrite = BytesLeft(bufPtr);
 	if (toWrite == 0) {
+	    /* TODO: This cannot happen. */
 	    written = 0;
 	} else {
 	    written = (chanPtr->typePtr->outputProc)(chanPtr->instanceData,
@@ -2667,6 +2668,8 @@ FlushChannel(
 	    ReleaseChannelBuffer(bufPtr);
 	    continue;
 	} else {
+	    /* TODO: Consider detecting and reacting to short writes
+	     * on blocking channels.  Ought not happen.  See iocmd-24.2. */
 	    wroteSome = 1;
 	}
 
@@ -2700,6 +2703,12 @@ FlushChannel(
 	    ResetFlag(statePtr, BG_FLUSH_SCHEDULED);
 	    (chanPtr->typePtr->watchProc)(chanPtr->instanceData,
 		    statePtr->interestMask);
+	} else {
+	    /* TODO: If code reaches this point, it means a writable
+	     * event is being handled on the channel, but the channel
+	     * could not in fact be written to.  This ought not happen,
+	     * but Unix pipes appear to act this way (see io-53.4).
+	     * Also can imagine broken reflected channels. */
 	}
     }
 
diff --git a/tests/io.test b/tests/io.test
index c7da8e6..f1248b9 100644
--- a/tests/io.test
+++ b/tests/io.test
@@ -2786,7 +2786,7 @@ test io-29.34 {Tcl_Close, async flush on close, using sockets} {socket tempNotMa
     variable x running
     set l abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz
     proc writelots {s l} {
-	for {set i 0} {$i < 2000} {incr i} {
+	for {set i 0} {$i < 9000} {incr i} {
 	    puts $s $l
 	}
     }
@@ -2817,7 +2817,7 @@ test io-29.34 {Tcl_Close, async flush on close, using sockets} {socket tempNotMa
     close $ss
     vwait [namespace which -variable x]
     set c
-} 2000
+} 9000
 test io-29.35 {Tcl_Close vs fileevent vs multiple interpreters} {socket tempNotMac fileevent} {
     # On Mac, this test screws up sockets such that subsequent tests using port 2828
     # either cause errors or panic().