sys-file-reader: Reduce invalid format from error to warning.

[pspp] / doc / dev / system-file-format.texi

diff --git a/doc/dev/system-file-format.texi b/doc/dev/system-file-format.texi
index 6276b6de859f999f376e9ab139a80bb8ab3e4dd4..7b0eff9f79823f0bb623e10d2f1da8c22922eff7 100644 (file)
--- a/doc/dev/system-file-format.texi
+++ b/doc/dev/system-file-format.texi
@@ -391,6 +391,11 @@ Format types are defined as follows:
 @end multitable
 @end quotation
 
+A few system files have been observed in the wild with invalid
+@code{write} fields, in particular with value 0.  Readers should
+probably treat invalid @code{print} or @code{write} fields as some
+default format.
+
 @node Value Labels Records
 @section Value Labels Records