CALCURSE - text-based organizer

Abstract

This manual describes calcurse functionnalities, and how to use them. The installation from source is first described, together with the available command line arguments. The user interface is then presented, with all of the customizable options that change calcurse behavior. Last, bug reporting procedure is explained, as well as the way one can contribute to calcurse development.

Table of Contents

1. Introduction

calcurse is a text-based calendar and scheduling application. It helps keeping track of events, appointments and everyday tasks. A configurable notification system reminds user of upcoming deadlines, and the curses based interface can be customized to suit user needs. All of the commands are documented within an online help system.

2. Overview

2.1 Creation history

I started thinking about this project when I was finishing my Ph.D. in Astrophysics... It started to be a little hard to organize myself, and I really needed a good tool to help me in that difficult task ;)

I like programs which use Text User Interfaces, because they are simple, fast, portable and efficient, so I thought about working on coding a simple calendar using such an interface. Moreover, I wanted to go on learning the C language, which I only used for a while during my undergraduate studies. So I thought that would be the good project to start in order to get organized and to learn about a few C things !

Unfortunately, I finished my Ph.D. before finishing calcurse, but anyway, I still wanted to work on it, hoping it would be helpful to other people. So here it is...

But why 'calcurse' anyway ? Well, it is simply the concatenation of 'CALendar' and 'nCURSEs', the name of the library used to build the user interface.

2.2 Important features

Calcurse is multi-platform and intended to be lightweight, fast and reliable. It is to be used inside a console or terminal, locally or on a distant machine within an ssh (or similar) connection.

Calcurse can be run in two different modes : interactive or non-interactive mode. The first mode allows oneself to view its own personal organizer almost everywhere, thanks to the text-based interface. The second mode permits to easily build reminders just by adding calcurse with appropriate command line arguments inside a cron tab or within a shell init script.

Moreover, calcurse was created with the end-user in mind, and tends to be as friendly as possible. This means a complete on-line help system, together with having all of the possible actions displayed at any time inside a status bar. The user interface is also configurable, and one can choose between several color and layout combinations. Last, a configurable notification system reminds user of upcoming appointments.

3. Installation

3.1 Requirements

3.1.1 ncurses library

Calcurse requires only a C compiler, such as cc or gcc, and the ncurses library. It would be very surprising not to have a valid ncurses library already installed on your computer, but if not, you can find it at the following url :

http://ftp.gnu.org/pub/gnu/ncurses/

3.1.2 gettext library

calcurse supports internationalization (i18n hereafter) through the gettext utilities. This means calcurse can produce multi-lingual messages if compiled with native language support (i.e. NLS).

However, NLS is optionnal and if you do not want to have support for multi-lingual messages, you can disable this feature. This is done by giving the --disable-nls option to configure (see section Install process). To check if the gettext utilities are installed on your system, you can search for the libintl.h header file for instance:

locate libintl.h

If this header file is not found, then you can obtain the gettext sources at the following url :

http://ftp.gnu.org/pub/gnu/gettext/

Note: Even if libintl.h is found on your system, it can be wise to specify its location during the install process, by using the --with-libintl-prefix option with configure. Indeed, the configure could fail to locate this library if installed in an uncommon place.

3.2 Install process

First you need to gunzip and untar the source archive:

tar zxvf calcurse-2.1.tar.gz

Once you meet the requirements and have extracted the archive, the install process is quite simple, and follows the standard three steps process:

  1. ./configure
  2. make
  3. make install (may require root privilege)

Use ./configure --help to obtain a list of possible options.

4. calcurse basics

4.1 Invocation

4.1.1 Command line arguments

calcurse takes the following options from the command line (both short and long options are supported):

-a, --appointment
Print the appointments and events for the current day and exit.

Note: the calendar from which to read the appointments can be specified using the '-c' flag.

-c <file>, --calendar <file>
Specify the calendar file to use. The default calendar is ~/.calcurse/apts (see section calcurse files).
-d <date|num>, --day <date|num>
Print the appointments for the given date or for the given number of upcoming days, depending on the argument format. Two possible formats are supported:
  • a date of the form 'mm/dd/yyyy'.
  • a number 'n'.
In the first case, the appointment list for the specified date will be returned, while in the second case the appointment list for the 'n' upcoming days will be returned. As an example, typing calcurse -d 3 will display your appointments for today, tomorrow, and the day after tomorrow.

Note: as for the '-a' flag, the calendar from which to read the appointments can be specified using the '-c' flag.

-h, --help
Print a short help text describing the supported command-line options, and exit.
-n, --next
Print the next appointment within upcoming 24 hours and exit. The indicated time is the number of hours and minutes left before this appointment.

Note: the calendar from which to read the appointments can be specified using the '-c' flag.

-N, --note
When used with the '-a' or '-t' flag, also print note content if one is associated with the displayed item.
-t[num], --todo[=num]
Print the 'todo' list and exit. If the optional number num is given, then only todos having a priority equal to num will be returned.

Note: proprity number must be between 1 (highest) and 9 (lowest).

-v, --version
Display calcurse version and exit.
-x, --export
Export user data to iCalendar format. Events, appointments and todos are converted and echoed to stdout.

Note: redirect standard output to export data to a file, by issuing a command such as: $ calcurse --export > my_data.ics

4.1.2 Environment variable for i18n

calcurse can be compiled with native language support (see gettext library). Thus, if you wish to have messages displayed into your native language, first make sure it is available by looking at the po/LINGUAS file. This file indicates the set of available languages by showing the two-letters corresponding code (for exemple, fr stands for french). If you do not find your language, it would be greatly appreciated if you could help translating calcurse (see the How to contribute? section).

If your language is available, run calcurse with the following command:

LC_ALL=fr_FR calcurse

where fr_FR is the locale name in this exemple, but should be replaced by the locale corresponding to the desired language.

You should also specify the charset to be used, because in some cases the accents and such are not displayed correctly. This charset is indicated at the beginning of the po file corresponding to the desired language. For instance, you can see in the fr.po file that it uses the iso-8859-1 charset, so you could run calcurse using the following command:

LC_ALL=fr_FR.ISO8859-1 calcurse

4.1.3 Other environment variables

The following environment variables affect the way calcurse operates:

VISUAL
Specifies the external editor to use for writing notes.
EDITOR
If the VISUAL environment variable is not set, then EDITOR will be used as the default external editor. If none of those variables are set, then /usr/bin/vi is used instead.
PAGER
Specifies the default viewer to be used for reading notes. If this variable is not set, then /usr/bin/less is used.

4.2 User interface

4.2.1 Non-interactive mode

When called with at least one of the following arguments: -a, -d, -h, -n, -t, -v, -x, calcurse is started in non-interactive mode. This means the desired information will be displayed, and after that, calcurse simply quits and you are driven back to the shell prompt.

That way, one can add a line such as 'calcurse --todo --appointment' in its init config file to display at logon the list of tasks and appointments scheduled for the current day.

4.2.2 Interactive mode

When called without any argument or only with the -c option, calcurse is started in interactive mode. In this mode, you are shown an interface containing three different panels which you can browse using the 'TAB' key, plus a notification bar and a status bar (see figure below).


 appointment panel---.                                   .---calendar panel
                     |                                   |  
                     v                                   v
 +------------------------------------++----------------------------+
 |          Appointments              ||          Calendar          |
 |------------------------------------||----------------------------|
 |                 (|)  April 6, 2006 ||         April 2006         |
 |                                    ||Mon Tue Wed Thu Fri Sat Sun |
 |                                    ||                      1   2 |
 |                                    ||  3   4   5   6   7   8   9 |
 |                                    || 10  11  12  13  14  15  16 |
 |                                    || 17  18  19  20  21  22  23 |
 |                                    || 24  25  26  27  28  29  30 |
 |                                    ||                            |
 |                                    |+----------------------------+
 |                                    |+----------------------------+
 |                                    ||            ToDo            | todo
 |                                    ||----------------------------| panel
 |                                    ||                            |   |
 |                                    ||                            |   |
 |                                    ||                            |<--.
 |                                    ||                            |
 +------------------------------------++----------------------------+
 |---[ Mon 2006-11-22 | 10:11:43 ]---(apts)----> 01:20 :: lunch <---|<--.
 +------------------------------------------------------------------+ notify-bar
 | ? Help     R Redraw    H/L -/+1 Day      G GoTo       C Config   | 
 | Q Quit     S Save      J/K -/+1 Week   Tab Chg View              |<-. 
 +------------------------------------------------------------------+  |
                                                                       |
                                                                 status bar

The first panel represents a calendar which allows to highlight a particular day, the second one contains the list of the events and appointments on that day, and the last one contains a list of tasks to do but which are not assigned to any specific day.

In the appointment panel, one can notice the '(|)' sign just in front of the date. This indicates the current phase of the moon. Depending on which is the current phase, the following signs can be seen:

' |) ':
first quarter
' (|) ':
full moon
' (| ':
last quarter
' | ':
new moon
no sign:
phase of the moon does not correspond to any of the above ones

At the very bottom of the screen there is a status bar, which indicates the possible actions and the corresponding keystrokes.

Just above this status bar is the notify-bar, which indicates from left to right : the current date, the current time, the calendar file currently in use (apts on the above example, which is the default calendar file, see the following section), and the next appointment within the upcoming 24 hours. Here it says that it will be lunch time in one hour and twenty minutes.

Note: Some actions, such as editing or adding an item, require to type in some text. This is done with the help of the built-in input line editor.

Within this editor, if a line is longer than the screen width, a '>', '*', or '<' character is displayed in the last column indicating that there are more character after, before and after, or before the current position, respectively. The line is scrolled horizontally as necessary.

Moreover, some editing commands are bound to particular control characters. Hereafter are indicated the available editing commands ('^' stands for the control key):

^a:
moves the cursor to the beginning of the input line
^b:
moves the cursor backward
^d:
deletes one character forward
^e:
moves the cursor to the end of the input line
^f:
moves the cursor forward
^h:
deletes one character backward
^k:
deletes the input from the cursor to the end of the line
ESCAPE:
cancels the editing

4.3 calcurse files

The following structure is created in your $HOME directory the first time calcurse is run :

$HOME/.calcurse/
           |___notes/
           |___conf
           |___apts
           |___todo
notes/:
this subdirectory contains descriptions of the notes which are attached to appointments, events or todos. One text file is created per note, whose name is built using mkstemp(3) and should be unique, but with no relation with the corresponding item's description.
conf:
this file contains the user configuration
apts:
this file contains all of the events and user's appointments
todo:
this file contains the todo list

4.4 Online help

At any time, the built-in help system can be invoked by pressing the '?' key. Once viewing the help screens, informations on a specific command can be accessed by pressing the keystroke corresponding to that command.

5. Options

All of the calcurse parameters are configurable from the Configuration menu available when pressing 'C'. You are then driven to a submenu with four possible choices : pressing 'C' again will lead you to the Color scheme configuration, pressing 'L' allows you to choose the layout of the main calcurse screen (in other words, where to put the three different panels on screen), pressing 'G' permits you to choose between different general options, and last you can modify the notify-bar settings by pressing 'N'.

5.1 General options

These options control calcurse general behavior, as described below:

auto_save (default: yes)
This option allows to automatically save the user's data (if set to yes) when quitting.

warning: No data will be automatically saved if auto_save is set to no. This means the user must press 'S' (for saving) in order to retrieve its modifications.

confirm_quit (default: yes)
If set to yes, confirmation is required before quitting, otherwise pressing 'Q' will cause calcurse to quit without prompting for user confirmation.
confirm_delete (default: yes)
If this option is set to yes, pressing 'D' for deleting an item (either a todo, appointment, or event), will lead to a prompt asking for user confirmation before removing the selected item from the list. Otherwise, no confirmation will be needed before deleting the item.
skip_system_dialogs (default: no)
Setting this option to yes will result in skipping the system dialogs related to the saving and loading of data. This can be useful to speed up the input/output processes.
skip_progress_bar (default: no)
If set to yes, this will cause the disappearing of the progress bar which is usually shown when saving data to file. If set to no, this bar will be displayed, together with the name of the file being saved (see section calcurse files).
week_begins_on_monday (default: yes)
One can choose between Monday and Sunday as the first day of the week. If the option week_begins_on_monday is set to yes, Monday will be first in the calendar view. Else if the option is set to no, then Sunday will be the first day of the week.

5.2 Color themes

calcurse color theme can be customized to suit user's needs. To change the default theme, the configuration page displays possible choices for foreground and background colors. Using arrows or calcurse displacement keys to move, and 'X' or space to select a color, user can preview the theme which will be applied. It is possible to keep the terminal's default colors by selecting the corresponding choice in the list.

The chosen color theme will then be applied to the panel borders, to the titles, to the keystrokes, and to general informations displayed inside status bar. A black and white theme is also available, in order to support non-color terminals.

Notes: Depending on your terminal type and on the value of the $TERM environnement variable, color could or could not be supported. An error message will appear if you try to change colors whereas your terminal does not support this feature. If you do know your terminal supports colors but could not get calcurse to display them, try to set your $TERM variable to another value (such as xterm-xfree86 for instance).

5.3 Layout configuration

The layout corresponds to the position of the panels inside calcurse screen. The default layout makes the calendar panel to be displayed on the top-right corner of the terminal, the todo panel on the bottom-right corner, while the appointment panel is displayed on the left hand-side of the screen (see the figure in section Interactive mode for an exemple of the default layout). By choosing another layout in the configuration screen, user can customize calcurse appearence to best suit his needs by placing the different panels where needed.

5.4 Notify-bar settings

The following options are used to modify the notify-bar behavior:

notify-bar_show (default: yes)
This option indicates if you want the notify-bar to be displayed or not.
notify-bar_date (default: %a %F)
With this option, you can specify the format to be used to display the current date inside the notification bar. You can see all of the possible formats by typing man 3 strftime inside a terminal.
notify-bar_time (default: %T)
With this option, you can specify the format to be used to display the current time inside the notification bar. You can see all of the possible formats by typing man 3 strftime inside a terminal.
notify-bar_warning (default: 300)
When there is an appointment which is flagged as 'important' within the next 'notify-bar_warning' seconds, the display of that appointment inside the notify-bar starts to blink. Moreover, the command defined by the notify-bar_command option will be launched. That way, the user is warned and knows there will be soon an upcoming appointment.
notify-bar_command (default: printf '\a')
This option indicates which command is to be launched when there is an upcoming appointment flagged as 'important'. This command will be passed to the user's shell which will interpret it. To know what shell must be used, the content of the $SHELL environment variable is used. If this variable is not set, /bin/sh is used instead.

Example: Say the mail command is available on the user's system, one can use the following command to get notified by mail of an upcoming appointment (the appointment description will also be mentioned in the mail body):

calcurse --next | mail -s "[calcurse] upcoming appointment!" user@host.com

6. Known bugs

Incorrect highlighting of items appear when using calcurse black and white theme together with a $TERM variable set to xterm-color. To fix this bug, and as advised by Thomas E. Dickey (xterm maintainer), xterm-xfree86 should be used instead of xterm-color to set the $TERM variable:

"The xterm-color value for $TERM is a bad choice for XFree86 xterm because it is commonly used for a terminfo entry which happens to not support bce. Use the xterm-xfree86 entry which is distributed with XFree86 xterm (or the similar one distributed with ncurses)."

7. Reporting bugs and feedback

Please send bug reports and feedback to:

calcurse .at. culot .dot. org

or to the author:

frederic .at. culot .dot. org

8. How to contribute?

If you would like to contribute to the project, you can first send your feedback on what you like or dislike, and if there are features you miss in calcurse. For now on, possible contributions concern the translation of calcurse messages and documentation.

Note: any help in getting calcurse internationalized would be very welcomed, but before contributing, send a mail to calcurse-i18n .at. culot .dot. org to know if someone already started the translation process into your language.

8.1 Translating documentation

The doc/ directory of the source package already contains translated version of calcurse manual. However, if the manual is not yet available into your native language, it would be appreciated if you could help translating it.

To do so, just copy one of the existing manual file to manual_XX.html, where XX identifies your language. Then translate this newly created file and send it to the author (see Reporting bugs and feeback), so that it can be included in the next calcurse release.

8.2 calcurse i18n

As already mentioned, gettext utilities are used by calcurse to produce multi-lingual messages. This section provides informations about how to translate those messages into your native language. However, this howto is deliberately incomplete, focusing on working with gettext for calcurse specifically. For more comprehensive informations or to grasp the Big Picture of Native Language Support, you should refer to the GNU gettext manual at:

http://www.gnu.org/software/gettext/manual/

Basically, three different people get involved in the translation chain: coders, language coordinator, and translators. After a quick overview of how things work, the translator tasks will be described hereafter.

8.2.1 Overview

To be able to display texts in the native language of the user, two steps are required: internationalization (i18n) and localization (l10n).

i18n is about making calcurse support multiple languages. It is performed by coders, who will mark translatable texts and provide a way to display them translated at runtime.

l10n is about making the i18n'ed calcurse adapt to the specific language of the user, ie translating the strings previously marked by the developers, and setting the environment correctly for calcurse to use the result of this translation.

So, translatable strings are first marked by the coders within the C source files, then gathered in a template file (calcurse.pot - the pot extension meaning portable object template). The content of this template file is then merged with the translation files for each language (fr.po for french, for instance - with po standing for portable object, ie meant to be read and edited by humans). A given translation team will take this file, translate its strings, and send it back to the developers. At compilation time, a binary version of this file (for efficiency reasons) will be produced (fr.mo - mo stands for machine object, ie meant to be read by programs), and then installed. Then calcurse will use this file at runtime, translating the strings according to the locale settings of the user.

8.2.2 Translator tasks

Suppose someone wants to initiate the translation of a new language. Here are the steps to follow:

Now, having this fr.po file, the translator is ready to begin.

8.2.3 po-files

The format of the po-files is quite simple. Indeed, po-files are made of four things:

  1. location lines: tells you where the strings can be seen (name of file and line number), in case you need to see a bit of context.
  2. msgid lines: the strings to translate.
  3. msgstr lines: the translated strings.
  4. lines prefixed with '#': comments (some with a special meaning, as we will see below).

Basically, all you have to do is fill the msgstr lines with the translation of the above msgid line.

A few notes:

Fuzzy strings
You will meet strings marked with a "#, fuzzy" comment. calcurse won't use the translations of such strings until you do something about them. A string being fuzzy means either that the string has already been translated but has since been changed in the sources of the program, or that this is a new string for which gettext made a 'wild guess' for the translation, based on other strings in the file. It means you have to review the translation. Sometimes, the original string has changed just because a typo has been fixed. In this case, you won't have to change anything. But sometimes, the translation will no longer be accurate and needs to be changed. Once you are done and happy with the translation, just remove the "#, fuzzy" line, and the translation will be used again in calcurse.
c-format strings and special sequences
Some strings have the following comment: "#, c-format". This tells that parts of the string to translate have a special meaning for the program, and that you should leave them alone. For instance, %-sequences, like "%s". These means that calcurse will replace them with another string. So it is important it remains. There are also \-sequences, like \n or \t. Leave them, too. The former represents an end of line, the latter a tabulation.
Translations can be wrapped
If lines are too long, you can just break them like this: 
msgid ""
"some very long line"
"another line"
po-file header
At the very beginning of the po-file, the first string form a header, where various kind of information has to be filled in. Most important one is the charset. It should resemble 
"Content-Type: text/plain; charset=utf-8\n"
You should also fill in the Last-Translator field, so that potential contributors can contact you if they want to join you in the translation team, or have remarks/typo fixes to give about the translations. You can either just give your name/nick, or add an email address, for exemple: 
"Last-Translator: Frederic Culot <frederic@culot.org>\n"
Comments
Adding comments (lines begining with the '#' character) can be a good way to point out problems or translation difficulties to proofreaders or other members of your team.
Strings size
calcurse is a curses/console program, thus it can be heavily dependant on the terminal size (number of columns). You should think about this when translating. Often, a string must fit into a single line (standard length is 80 characters). Don't translate blindly, try to look where your string will be displayed to adapt your translation.
A few useful tools
The po-file format is very simple, and the file can be edited with a standard text editor. But if you prefer, there are few specialized tools you may find convenient for translating:
And finally
I hope you'll have fun contributing to a more internationalized world. :) If you have any more questions, don't hesitate to contact me at frederic .at. culot .dot. org.

9. Links

This section contains links and references that may be of interest to you.

9.1 calcurse homepage

The calcurse homepage can be found at 

http://culot.org/calcurse

9.2 calcurse announce list

If you are interested in the project and want to be warned when a new release comes out, you can subscribe to the calcurse announce list. In doing so, you will receive an email as soon as a new feature appears in calcurse.

To subscribe to this list, send a message to calcurse-announce .at. culot .dot. org with "subscribe" in the subject field.

9.3 calcurse RSS feed

Another possibility to get warned when new releases come out is to follow the RSS feed at:

http://culot.org/calcurse/news_rss.xml

This RSS feed is updated each time a new version of calcurse is available, describing newly added features.

10. Thanks

Its time now to thank other people without whom this program would not exist! So here is a list of contributing persons I would like to thank :

And last, many many thanks to all of the calcurse users who sent me their feedback.

Copyright (c) 2004-2008 Frédéric Culot
Calcurse version 2.1 - Last change: April 05, 2008