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diff --git a/man/1/charon b/man/1/charon new file mode 100644 index 00000000..abfdede6 --- /dev/null +++ b/man/1/charon @@ -0,0 +1,442 @@ +.TH CHARON 1 +.SH NAME +charon \- web browser +.SH SYNOPSIS +.B charon +[ +.BI - option +.RI [ value ] +] +.RI [ url ] +.SH DESCRIPTION +.I Charon +is the Inferno graphical web browser, supporting a variety of web standards for +the download, viewing, automation and navigation of web based information and images. +.PP +The browser runs under the +.IR wm (1) +window manager, or directly on the +.IR draw (3) +and +.IR cons (3) +devices. +When +.I charon +starts, it checks to see if +.I wm +is running; if it is then +.I charon +creates a new +.I wm +window for its display, otherwise it uses the whole area of the display device. +.PP +.I Charon +implements an image cache to help reduce the overhead of revisiting pages. +The image cache resides in memory for the duration of a session. +The cache is managed by discarding least recently used images once the cache bounds +have been reached. +Currently, +.I charon +does not provide a general purpose web cache; all other resources have to be reloaded +when needed. +.SS Navigation +.I Charon +provides navigation controls familiar to any web-surfer: +back, forward, reload, home, stop and URL entry. +Navigation of web-based information is by means of following HTML +.IR links, +this is done by clicking on them using mouse button-1, or the touch-screen. +Clicking mouse button-2 on a link causes its address to be displayed in the +.I status +line of +.IR charon 's +display. +Navigation to other information is achieved by clicking on the URL entry +field and typing the address of the resource, followed by the Enter key. +.PP +The retrieval and processing of the current page +is immediately terminated by clicking the Stop button. +.PP +As resources are browsed, a history of their web addresses (URLs) is built up. +At any time you can navigate forwards and backwards through this list using +the Forward and Back buttons. +Additionally, clicking the History button, displays the entire history list as a set of +.I links +enabling the user to quickly jump to any position in the list. +.PP +Sometimes, it is not possible to retrieve all of the components of a web document at the time +that it is requested. +Often this is because the remote server is very busy or not available. +This can result in the presentation of the document being incomplete or even corrupted. +Clicking the Reload button causes +.I charon +to attempt to retrieve the current document and all of its components again. +.PP +.I Charon +displays a progress panel to indicate the download status of each of the components of the +current document. +The progress panel is displayed at the bottom of the +.I charon +window. +Each component of the current document is represented by a rectangular block in the +progress panel. +As the download of a component progresses, its corresponding block is gradually filled in. +If an error occurs while downloading or processing the component, its block is coloured red. +The component address and amount downloaded, or reason for failure, can +be obtained by clicking mouse button-1 on its progress block. +.SS "Web Standards" +Standards are the life-blood of the World-Wide-Web; +without them, the web could not exist. +Web standards are under constant review with revised editions and complete new standards +being published all of the time. +This section lists the standards supported by +.I charon +at the time of writing this manual entry. +The version of the standard is given, if appropriate, alongside any comments on its +implementation. +.PP +.TP 15 +Protocols +HTTP versions 1.0 and 1.1 +.IP +HTTPS: SSL Protocol versions 2.0 and 3.0. +X.509.v3 server certificates. +.IP +FTP: +.I charon +supports retrieval of plain text files only, directory listings are not generated. +.IP +FILE: +.I Charon +attempts to determine the file type by a combination of the filename extension and +examination of the first few bytes of the file. Directory listings are not generated. +.TP +HTML +It is intended that +.I charon +supports HTML version 3.2, but in reality there is +no single standard! +.I Charon +attempts to be as close as possible to Netscape Navigator Version 3 in terms of its +markup support. +Obvious bugs in Navigator 3 and +the Netscape security model have not been adopted. +.TP +JavaScript +.I Charon +implements ECMAscript-262 2nd Edition, which is roughly equivalent to JavaScript1.1. +The ECMA-262 standard does not define the +.I host +objects and classes that should implemented by the browser. +.I Charon +implements the set of host objects and classes of Netscape Navigator version 3. +.TP +Encodings +US_Ascii, ISO_8859_1, UTF_8, Unicode (big-endian) +.TP +Images +GIF87a and GIF89a - animated GIFs always loop. +.br +JPEG, XBitmap, +Inferno BIT +.IR image (6) +format. +.SS Configuration +While using +.IR charon , +a sub-set of the configuration options can be modified. +Clicking the Configuration button displays a config popup window, enabling the user +to modify the current values of the available options. +.PP +The full set of configuration options can be modified on the command line or in +a configuration file. +Comand line options are processed after the configuration file. +The configuration file is loaded from +.BI /usr/ user /charon/config +where +.I user +is obtained by reading the file +.BR /dev/user . +If this file does not exist, the file +.B /services/config/charon.cfg +is read instead. +Options are processed in order; some options override settings affected +by others and so the order in which they are used is important. +.PP +Options are specified using a +.IR key , +.I value +pair. +On the command line this takes the form: +.IP +.BI - key +.I value +.PP +Where +.BI - key +and +.I value +are individual items in the argument list to +.IR charon . +.PP +In the config file options take the form: +.IP +.IB key = value +.PP +Where +.I value +is the remainder of the input line after the +.BR ` = ' +character. +Any text lines in the config file that start with a +.RB ` # ' +character are ignored as comment lines. +.SH OPTIONS +.TF 10 +.TP +.B userdir +The directory where +.I charon +expects to find its configuration files such as, bookmark and cookie files. +The default value is +.BI /usr/ user /charon/ +where +.I user +is obtained by reading the file +.BR /dev/user . +.TP +.B starturl +Specifies the URL of the first document to be displayed by +.I charon +at startup. +The default value is +.B file://localhost/services/webget/start.html +.TP +.B homeurl +Specifies the URL of the document to retrieve when the Home button is clicked. +The homeurl can only be changed if the +.B change_homeurl +option is enabled. +Setting +.B homeurl +also set the value of the +.B starturl +option. +The default value is +.B file://localhost/services/webget/start.html +.TP +.B change_homeurl +Enables editing of the Home URL in the configuration popup window. +A non-zero integer value enables this option, all other values disable it +This option also enables the +.B homeurl option. +The default value is 1. +.TP +.B helpurl +Specifies the URL of the document to retrieve when the Help button is clicked. +The default value is +.B file://localhost/services/webget/help.html +.TP +.B httpproxy +Specifies the host name and port of a web proxy server. +The address is given in the form of a URL, where the optional port number +can be specified after the server name by separating them by a colon +.RB ` : '. +The default value is the empty string, specifying that no web proxy server should be used. +.TP +.BI noproxy " or " noproxydoms +Specifies a list of network domains for which a web proxy should not be used. +The domains in the list can be separated by semicolon, comma, space or tab characters. +The default value is the empty list. +.TP +.B usessl +Extends SSL support. +Accepted values are +.RB `` v2 '' +and +.RB `` v3 ''. +Initially SSL support is configured off. +Enabling version 1 or version 2 support restricts SSL support to that specific version. +Specifying the option twice, once with each of the options, enables dual version +SSL support whereby the remote server is probed to determine which version it supports. +Some servers only support one of the versions and may not tolerate the special +version2/3 probe. +.TP +.B buttons +Specifies the set of buttons that appear on the window manager title-bar. +The buttons are given as a list of button names separated by comma, space or tab characters. +Valid button names are +.BR help , +.B resize +and +.BR hide . +The default value is for all buttons to be displayed. +.TP +.BI defaultwidth " or " width +Set the initial window width. +This option is only meaningful when running under the window manager. +If the specified width exceeds the screen width then the screen width is used. +The default value is 630. +.TP +.BI defaultheight " or " height +Set the initial height of the main display panel, this does not include the height +of the control and progress panels. +This option is only meaningful when running under the window manager. +If the total height of the +.I charon +window exceeds the screen height, the main display panel height will be reduced to fit. +The default value is 450. +.TP +.BI x " and/or " y +Set the initial window position. +These options are only meaningful when running under the window manager. +The default value for both options is 0. +.TP +.B imagelvl +Specify how to handle image components of a document. +This option takes a numeric argument. +A value of 0 prevents images from being downloaded or displayed. +A value of 1 will download and display images but not animate GIFS - only the first +frame of an animated GIF will be displayed. +A value of 2 or more enables full image processing. +The default value enables full image processing. +.TP +.B imagecachenum +Specify the maximum number of images that can remain resident in the image cache. +The default value is 60. +.TP +.B imagecachemem +Specify the maximum amount of image memory available to the image cache in bytes. +The cache is managed such that neither the +.B imagecachenum +nor +.B imagecachemem +limits are exceeded. +The image cache tries to ensure that no more than 80% of available system image memory +is taken by the cache, irrespective of the value of this option. +The default value is 80% of the system image memory that was available +.I when charon was started. +.TP +.B docookies +Enable cookie handling. +A non-zero numeric value enables cookie handling, all other values disable it. +The cookie cache is maintained in the +.B cookies +file in the +.I userdir +directory. +The default value is 0, cookie handling disabled. +.TP +.B doscripts +Enable JavaScript support. +A non-zero numeric value enables JavaScript, all other values disable it. +The default value is 0, JavaScript processing disabled. +.TP +.B showprogress +A non-zero numeric value results in the progress panel being displayed. +All other values hide the progress panel, leaving more vertical space for the main +display area. +The default value is 1, causing the progress panel to be displayed +.TP +.B http +Set the version of HTTP to use when communicating with web servers. +Supported versions are 1.0 and 1.1. +Any value other than 1.1 results in HTTP1.0 being used. +The default value is 1.0. +.TP +.B nthreads +Specifies the maximum number of concurrent downloads of document components. +Generally, if this number is higher, pages will complete faster as +.I charon +will not have to wait for the download of one component to complete before another +can be started. +The downside is that a higher number of concurrent downloads will use more memory +during the download process. +The default value is 4. +.SH FILES +.TF /services/config/charon.cfg +.TP +.B /services/config/charon.cfg +The default configuration file. +.TP +.IB userdir /config +The +.I user +specific configuration file. +.I userdir +is given by the value of the +.B userdir +option. +.TP +.IB userdir /cookies +The cookie cache. +.I userdir +is given by the value of the +.B userdir +option. +.TP +.B /services/webget/start.html +The default start page. +.TP +.B /services/webget/help.html +The default help page. +.SH SOURCE +.TF /appl/lib/ecmascript/ +.TP +.B /appl/charon/ +The main +.I charon +source files. +.TP +.B /appl/lib/ecmascript/ +Javascript (ECMA-262) implementation. +.SH BUGS +.I Charon +has more than its fair share of real bugs. +The following list documents the problems that are most likely to be +encountered. +.PP +.I Charon +implements its table layout as per the algorithm described in rfc1942. +This sometimes results in table-based documents being laid out differently to other +browsers. +.PP +JavaScript is a source of many problems. +Many scripts do not specify the language version they employ. +Additionally different language versions and browsers imply +a different set of +.I host +objects and classes. +Such differences often give rise to syntax or null reference errors. +This whole situation places a great burden on the script author to write +safe and compliant scripts; unfortunately authors +are rarely aware of this burden! +.PP +The following elements of JavaScript1.1 are not fully implemented: +.PP +.BR Document.applets , +.B Document.embeds +.I and +.BR Document.plugins : +Java Applets are not supported, the arrays are always empty. +.PP +.BR Document.onunload : +The property exists and can be assigned to, but the event is never raised. +.PP +.BR Window.open() : +A new window is never opened. If a URL is specified for the new window, the +current document will be replaced with that of the new URL. +.PP +Other annoyances include: +.PP +Window resize forces a complete document reload. +.PP +Frames in a frameset are processed one at a time, not concurrently. +.PP +It is not possible to save downloaded data to file. This is particularly annoying +for MIME types that +.I charon +does not support. +.PP +The history list can get confused, especially when following links in framesets +before the complete frameset has been downloaded. |