#15840: make docs consistent by saying operations on closed files raise ValueError.
Patch by Caelyn McAulay.
Neither Caelyn nor I could find any cases in 2.7 or 3.4/5 where an
operation on a closed stream raised IOError; generally the C
implementations have a macro to check for the stream being closed, and
these macros all raised ValueError. If we find any, a new bug should
be opened.
diff --git a/Modules/_io/iobase.c b/Modules/_io/iobase.c
index e372990..ef06b43 100644
--- a/Modules/_io/iobase.c
+++ b/Modules/_io/iobase.c
@@ -42,8 +42,8 @@
"bytes. bytearrays are accepted too, and in some cases (such as\n"
"readinto) needed. Text I/O classes work with str data.\n"
"\n"
- "Note that calling any method (even inquiries) on a closed stream is\n"
- "undefined. Implementations may raise IOError in this case.\n"
+ "Note that calling any method (except additional calls to close(),\n"
+ "which are ignored) on a closed stream should raise a ValueError.\n"
"\n"
"IOBase (and its subclasses) support the iterator protocol, meaning\n"
"that an IOBase object can be iterated over yielding the lines in a\n"