Add notes on our globs' incompatibilities with POSIX

[originally from svn r4149]

diff --git a/wildcard.c b/wildcard.c
index a09f2c1dbff7b1c978b0efd3a70268902c54f83a..ae8bad80a675d4ddc12633499996e061390f7cb2 100644 (file)
--- a/wildcard.c
+++ b/wildcard.c
@@ -29,6 +29,17 @@
  *  - All other characters are non-special and match themselves.
  */
 
+/*
+ * Some notes on differences from POSIX globs (IEEE Std 1003.1, 2003 ed.):
+ *  - backslashes act as escapes even within [] bracket expressions
+ *  - does not support [!...] for non-matching list (POSIX are weird);
+ *    NB POSIX allows [^...] as well via "A bracket expression starting
+ *    with an unquoted circumflex character produces unspecified
+ *    results". If we wanted to allow [!...] we might want to define
+ *    [^!] as having its literal meaning (match '^' or '!').
+ *  - none of the scary [[:class:]] stuff, etc
+ */
+
 /*
  * The wildcard matching technique we use is very simple and
  * potentially O(N^2) in running time, but I don't anticipate it