(main): If you can't open an output file (with seek=...) read-write,

then open it for write and report an error if we can't seek.

diff --git a/src/dd.c b/src/dd.c
index eebd214..09d5f44 100644 (file)
--- a/src/dd.c
+++ b/src/dd.c
@@ -1043,16 +1043,18 @@ main (int argc, char **argv)
 
   if (output_file != NULL)
     {
+      mode_t perms = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
+      int opts
+       = (O_CREAT
+          | (seek_record || (conversions_mask & C_NOTRUNC) ? 0 : O_TRUNC));
+
       /* Open the output file with *read* access only if we might
-        need to read to satisfy a `seek=' request.  */
-      int omode = (seek_record ? O_RDWR : O_WRONLY) | O_CREAT;
-
-      if (seek_record == 0 && !(conversions_mask & C_NOTRUNC))
-       omode |= O_TRUNC;
-      output_fd = open (output_file, omode,
-                       (S_IRUSR | S_IWUSR
-                        | S_IRGRP | S_IWGRP
-                        | S_IROTH | S_IWOTH));
+        need to read to satisfy a `seek=' request.  If we can't read
+        the file, go ahead with write-only access; it might work.  */
+      if (! seek_record
+         || (output_fd = open (output_file, O_RDWR | opts, perms)) < 0)
+       output_fd = open (output_file, O_WRONLY | opts, perms);
+
       if (output_fd < 0)
        error (1, errno, "%s", output_file);
 #if HAVE_FTRUNCATE