Prevent matching illegal sequences globally

E.g., a+b will no longer be matched by anything.  This is due to the
global usage of a modified list_all().

Also:
- Use different return types for different things (e.g. $RET_SUCCESS).
 `- Both internally and externally (exit codes, documented in ctct(1)).
- Make --search-by-data more efficient.
 `- One call to grep for all files.
 `- The conjunction of the regexes still requires several calls.
- Rename functions to more speaking names.
- Document the function parameters.
- Add vi modelines.
- Use [[:alpha:]] instead of [A-Za-z] which appears to be the same but
  more clear.  Notably, both seem to include non-ASCII letters, for
  example 'à'.
- Set nullglob option in the script to prevent errors for cases where
  glob patterns would be used.
- Add a silent option ro check_syntax() (not used).
- Add a full_path option to list_all() (not used).
- Use return instead of exit in main().
- Remove one remaining usage of eval.
- Fix small format issue in ctct(1) (I -> B).
 `- They are no longer, but it hardly harms to have this option.

1 files changed, 9 insertions, 0 deletions

diff --git a/configure.ac b/configure.ac
index 70cf150..dd45df4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -29,6 +29,13 @@ AC_CONFIG_FILES(
 AC_CONFIG_FILES([ctct], [chmod +x ctct])
 
 
+# ret_success must be 0, all others nonzero.
+AC_SUBST([ret_success], 0)
+AC_SUBST([ret_failure], 1)
+AC_SUBST([ret_badsyntax], 2)
+AC_SUBST([ret_error], 4)
+
+
 AC_ARG_VAR([bash_completion_dir],
 					 ['directory to store bash-completion script in'])
 test -z "$bash_completion_dir" \
@@ -95,3 +102,5 @@ test -z "$default_confirm_default_yes" \
 
 
 AC_OUTPUT
+
+# vi: ts=2 sw=2