* generic/tclIO.c (CopyData): Applied patch [Bug 1932639] to

	* tests/io.test: prevent fcopy from calling -command synchronously
	  the first time. Thanks to Alexandre Ferrieux
	  <ferrieux@users.sourceforge.net> for report and patch.

1 files changed, 23 insertions, 13 deletions

diff --git a/generic/tclIO.c b/generic/tclIO.c
index bf5eed5..aba2735 100644
--- a/generic/tclIO.c
+++ b/generic/tclIO.c
@@ -10,7 +10,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclIO.c,v 1.61.2.24 2008/04/02 20:27:58 andreas_kupries Exp $
+ * RCS: @(#) $Id: tclIO.c,v 1.61.2.25 2008/04/03 18:06:52 andreas_kupries Exp $
  */
 
 #include "tclInt.h"
@@ -7835,22 +7835,32 @@ CopyData(csPtr, mask)
 	    goto writeError;
 	}
 	
-	/*
-	 * Read up to bufSize bytes.
-	 */
+	if (cmdPtr && (mask == 0)) {
+	    /*
+	     * In async mode, we skip reading synchronously and fake an
+	     * underflow instead to prime the readable fileevent.
+	     */
 
-	if ((csPtr->toRead == -1) || (csPtr->toRead > csPtr->bufSize)) {
-	    sizeb = csPtr->bufSize;
+	    size      = 0;
+	    underflow = 1;
 	} else {
-	    sizeb = csPtr->toRead;
-	}
+	    /*
+	     * Read up to bufSize bytes.
+	     */
 
-	if (inBinary || sameEncoding) {
-	    size = DoRead(inStatePtr->topChanPtr, csPtr->buffer, sizeb);
-	} else {
-	    size = DoReadChars(inStatePtr->topChanPtr, bufObj, sizeb, 0 /* No append */);
+	    if ((csPtr->toRead == -1) || (csPtr->toRead > csPtr->bufSize)) {
+	        sizeb = csPtr->bufSize;
+	    } else {
+	        sizeb = csPtr->toRead;
+	    }
+
+	    if (inBinary || sameEncoding) {
+	        size = DoRead(inStatePtr->topChanPtr, csPtr->buffer, sizeb);
+	    } else {
+	        size = DoReadChars(inStatePtr->topChanPtr, bufObj, sizeb, 0 /* No append */);
+	    }
+	    underflow = (size >= 0) && (size < sizeb);	/* input underflow */
 	}
-	underflow = (size >= 0) && (size < sizeb);	/* input underflow */
 
 	if (size < 0) {
 	    readError: