X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=doc%2Fdev%2Fsystem-file-format.texi;h=4eb061580db5878b467fdbf4f6608f61d114972b;hb=38e6de480f30185dce6be3ad39668f4bfd5fd15d;hp=d100aa9d24d59fcd6265e73e70310d6b556403f8;hpb=ac196658f4fd578201d9feee087b02d95643b08e;p=pspp

diff --git a/doc/dev/system-file-format.texi b/doc/dev/system-file-format.texi
index d100aa9d24..4eb061580d 100644
--- a/doc/dev/system-file-format.texi
+++ b/doc/dev/system-file-format.texi
@@ -262,6 +262,10 @@ wider than 255 bytes.  Such very long string variables are represented
 by a number of narrower string variables.  @xref{Very Long String
 Record}, for details.
 
+A system file should contain at least one variable and thus at least
+one variable record, but system files have been observed in the wild
+without any variables (thus, no data either).
+
 @example
 int32               rec_type;
 int32               type;