In UNICOS and UNICOS/mk after a successful fcntl F_SETFL

of O_NONBLOCK a subsequent fcntl F_GETFL will return O_NDELAY.

p4raw-id: //depot/cfgperl@4904

diff --git a/ext/IO/IO.xs b/ext/IO/IO.xs
index e5ce83d..be84f73 100644 (file)
--- a/ext/IO/IO.xs
+++ b/ext/IO/IO.xs
@@ -62,23 +62,28 @@ io_blocking(InputStream f, int block)
        /* POSIX style */ 
 #if defined(O_NDELAY) && O_NDELAY != O_NONBLOCK
        /* Ooops has O_NDELAY too - make sure we don't 
-        * get SysV behaviour by mistake
-        */
-       RETVAL = RETVAL & O_NONBLOCK ? 0 : 1;
-
-       if ((mode & O_NDELAY) || ((block == 0) && !(mode & O_NONBLOCK))) {
-           int ret;
-           mode = (mode & ~O_NDELAY) | O_NONBLOCK;
-           ret = fcntl(PerlIO_fileno(f),F_SETFL,mode);
-           if(ret < 0)
-               RETVAL = ret;
-       }
-       else if ((mode & O_NDELAY) || ((block > 0) && (mode & O_NONBLOCK))) {
-           int ret;
-           mode &= ~(O_NONBLOCK | O_NDELAY);
-           ret = fcntl(PerlIO_fileno(f),F_SETFL,mode);
-           if(ret < 0)
-               RETVAL = ret;
+        * get SysV behaviour by mistake. */
+
+       /* E.g. In UNICOS and UNICOS/mk a F_GETFL returns an O_NDELAY
+        * after a successful F_SETFL of an O_NONBLOCK. */
+       RETVAL = RETVAL & (O_NONBLOCK | O_NDELAY) ? 0 : 1;
+
+       if (block >= 0) {
+           if ((mode & O_NDELAY) || ((block == 0) && !(mode & O_NONBLOCK))) {
+               int ret;
+               mode = (mode & ~O_NDELAY) | O_NONBLOCK;
+               ret = fcntl(PerlIO_fileno(f),F_SETFL,mode);
+               if(ret < 0)
+                   RETVAL = ret;
+           }
+           else
+              if ((mode & O_NDELAY) || ((block > 0) && (mode & O_NONBLOCK))) {
+               int ret;
+               mode &= ~(O_NONBLOCK | O_NDELAY);
+               ret = fcntl(PerlIO_fileno(f),F_SETFL,mode);
+               if(ret < 0)
+                   RETVAL = ret;
+              }
        }
 #else
        /* Standard POSIX */