commit: 7f4a0c4c7b45dfbb3ff064cd821380e8dade7534
Author: Michał Górny <mgorny <AT> gentoo <DOT> org>
AuthorDate: Thu Nov 23 18:37:39 2017 +0000
Commit: Michał Górny <mgorny <AT> gentoo <DOT> org>
CommitDate: Sat Nov 25 20:49:17 2017 +0000
URL: https://gitweb.gentoo.org/data/glep.git/commit/?id=7f4a0c4c
glep-0074: Always exclude control characters
glep-0074.rst | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/glep-0074.rst b/glep-0074.rst
index 8687969..6db6caa 100644
--- a/glep-0074.rst
+++ b/glep-0074.rst
@@ -138,10 +138,9 @@ Path and filename encoding
--------------------------
The path fields in the Manifest file must consist of characters
-corresponding to valid UTF-8 code points excluding the NULL character
-(``U+0000``), the backwards slash (``\``) and characters classified
-as whitespace in the current version of the Unicode standard
-[#UNICODE]_.
+corresponding to valid UTF-8 code points excluding the backwards slash
+(``\``) and characters classified as control characters and whitespace
+in the current version of the Unicode standard [#UNICODE]_.
Any of the excluded characters that are present in path must be encoded
using one of the following escape sequences:
@@ -164,8 +163,7 @@ slash used as path component separator should be replaced
by forward
slash instead.
The encoding can be used for other characters as well. In particular,
-escaping control characters is recommended to ensure that the file
-works correctly in text editors.
+escaping non-printable characters might be desirable.
File verification
@@ -593,16 +591,18 @@ This specification aims to avoid arbitrary restrictions.
For this
reason, filename characters are only restricted by excluding three
technically problematic groups:
-1. The NULL character (``U+0000``) is normally used to indicate the end
- of a null-terminated string. Its use could therefore break programs
- written using C. Furthermore, it is not allowed in any known
- filesystem.
-
-2. The backwards slash character (``\``) is used as path separator
+1. The backwards slash character (``\``) is used as path separator
on Windows systems, so it's extremely unlikely to be used in real
filenames. For this reason it is used to implement character
encoding with minimal risk of breaking backwards compatibility.
+2. The control characters can trigger special behavior in various
+ programs and confuse them from recognizing text files. In particular,
+ the NULL character (``U+0000``) is normally used to indicate the end
+ of a null-terminated string. Its use could therefore break
+ implementations written in the C language. Other control characters
+ could trigger various formatting routines, garbling text output.
+
3. Whitespace characters are used to separate Manifest fields
and entries. While technically it would be enough to restrict space
(``U+0020``) character that is normally used as the separator
