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, 2 insertions, 9 deletions

diff --git a/TODO b/TODO
index 1c732c5..01f78b8 100644
--- a/TODO
+++ b/TODO
@@ -1,16 +1,10 @@
 TODO file for ctct
 
 [GENERAL]
-* consider using an array for *_program to specify arguments
- `- to circumvent the necessity for eval
 * Honor $VISUAL.
+* Honor XDG user dirs.
 * Use git tags for future versions.
-* On `ctct -s <pattern>', do not match illegal sequences (e.g. a+b).
-* On `ctct -l', do only list legal names (e.g. not a+b).
-* Use the EXIT_* variables.
-* [consider] On `ctct -d', check format of string.
 * [consider] Remove character restriction except '.', '/'.
-* [consider] Use `grep -F' for --search-by-name.
 * [consider] Require at least one argument for --search-by-*.
 
 [CONFIGURE SCRIPT]
@@ -26,12 +20,11 @@ TODO file for ctct
  `- should be made customizable
 * [optional] Do not create a new entry if nothing is entered in the editor.
 * Support templates.
-* Different return types for errors and non-matches.
 * Quiet option for --search-by-*.
 * [consider] Use another default editor.
  `- nano, easily understandable.
  `- ed, the editor.
-* Honor XDG user dirs.
+* [consider] Use regexes for --search-by-name.
 
 [MANUAL]
 * Add an EXAMPLE section to ctct(1).