X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=elpher.texi;h=570c9fab1ebdef64f2cfd4d3504c5b138b856a7b;hb=e709905f4a3019372b2365e97019d7fd8741b125;hp=5fb4882f908366b24253a5bc3d18bd803c3846fb;hpb=c9ef766d6797cc27c6375011cab84ffd6e502ae8;p=elpher.git diff --git a/elpher.texi b/elpher.texi index 5fb4882..570c9fa 100644 --- a/elpher.texi +++ b/elpher.texi @@ -42,15 +42,17 @@ the file COPYING in the same directory as this file for more details. @menu * Introduction:: Elpher Overview: what's this all about? +* Installation:: Installing Elpher +* Quick Start:: Get up and running quickly * Navigation:: Fundamentals of Elpher navigation * Bookmarks:: How to record and visit bookmarks * Character encodings:: How Elpher handles different character encodings +* Encrypted connections:: How and when TLS is enabled * Customization:: How to customize various aspects of Elpher -* Hacking:: Contributing changes to Elpher * Index:: @end menu -@node Introduction, Navigation, Top, Top +@node Introduction, Installation, Top, Top @chapter Introduction Elpher aims to be a capable and practical gopher client for Emacs. Its @@ -84,9 +86,83 @@ this also means that any usability features that you feel are missing can likely by incoroporated quickly, so please get in touch if you have some ideas. -@node Navigation, Bookmarks, Introduction, Top -@chapter Navigation +@node Installation, Quick Start, Introduction, Top +@chapter Installation + +Elpher is available from the MELPA package repository. If you have +never installed packages from this repository before, you'll need +to follow the instructions at @url{https://melpa.org/#/getting-started}. + +@noindent To install Elpher, enter the following: + +@example +@kbd{M-x package-install @key{RET} elpher @key{RET}} +@end example + +@noindent To uninstall, use + +@example +@kbd{M-x package-delete @key{RET} elpher @key{RET}}. +@end example + +While not recommended, it is also possible to install Elpher directly by +downloading the file @file{elpher.el} from +@url{https://github.com/tgvaughan/elpher}, adding it to a directory in +your @code{load-path}, and then adding + +@example +(require 'elpher) +@end example + +@noindent to your Emacs initialization file. + +@node Quick Start, Navigation, Installation, Top +@chapter Quick Start + +Before diving into the minutiae of the different commands available, +we will quickly describe how to get up and running with Elpher. + +Once installed, you can launch Elpher using + +@example +@kbd{M-x elpher @key{RET}} +@end example + +@noindent This will switch to the *Elpher* buffer and display a start +page, with information on each of the default keyboard bindings. + +From here you can move point between links (which may be menu items or +inline URLs in text files) by using @key{TAB} and @kbd{S-@key{TAB}}, +as in Info. You can also jump directly to a menu item using @key{m}, or +use the standard Emacs or Evil motion and search commands to find your +way around. To open a link, press @key{RET}. (Where a mouse is +available, Clicking on a link with the mouse cursor has the same +effect.) + +To return to the page you just followed the link from, press @key{u}. + +Elpher caches (for the duration of an Emacs session) both page contents +and the position of point on each of the pages (gopher menus, query +results, or text pages) you visit, restoring these when you next visit +the same page. Thus, pressing @key{u} displays the previous page in +exactly the same state as when you left, meaning that you can quickly +and visually explore the different documents in a menu without having to +wait for anything to reload. +Of course, sometimes you'll @emph{want} to reload the current page +rather than stick with the cached version. To do this use @key{R}. +(This is particularly useful for search query results, where this +allows you to perform a different search.) + +That's more-or-less it. Elpher supports a number of other features, such +as bookmarking, support for different coding schemes and TLS encryption, +and a variety of customization options, all of which are explained in +the rest of this document. However the emphasis is on keeping the basic +navigation experience as intuitive and responsive as possible. + +@node Navigation, Bookmarks, Quick Start, Top +@chapter Navigation +by Throughout this manual, we use the word ``page'' to refer to any visualization of a response from a gopher server, be it a menu/directory, query result, text file or image. We use @@ -100,7 +176,8 @@ coupled with caching of pages and cursor position. @menu * Within-page navigation:: Moving about within a page -* Between-page navigation:: Concepts and commands for moving between pages +* Between-page navigation:: Commands for moving between pages +* History and Caching:: Explanation of how Elpher represents history @end menu @@ -115,10 +192,10 @@ In addition, the following commands are provided for quickly moving between links and menu items. @table @asis -@item @kbd{tab} (@code{elpher-next-link}) +@item @key{TAB} (@code{elpher-next-link}) Move to the next link or menu item in the file. -@item @kbd{}/@kbd{} (@code{elpher-prev-link}) +@item @kbd{Shift-@key{TAB}}/@key{backtab} (@code{elpher-prev-link}) Move to the previous link or menu item in the file. @item @kbd{m} (@code{elpher-jump}) @@ -144,10 +221,23 @@ system clipboard (if available). @item @kbd{C} (@code{elpher-copy-current-url}) Add URL representing address of the current page to the kill-ring and the system clipboard (if available). -@end table +@item @kbd{d} (@code{elpher-download}) +Download link at point and save the result as a file. The minibuffer +will prompt for the name of the file to write, with the default name being +the display string (if available) associated with the link. + +@item @kbd{D} (@code{elpher-download-current}) +This is similar to @code{elpher-downlowd}, but instead applies to the +current page rather than a link. + +@item @kbd{w} (@code{elpher-view-raw}) +This displays the raw server response for the current page. While not +useful for general browsing, it is useful for debugging incorrect rendering +or out-of-spec server responses. +@end table -@node Between-page navigation, , Within-page navigation, Navigation +@node Between-page navigation, History and Caching, Within-page navigation, Navigation @section Between-page navigation Moving to a different page can be accomplished in several ways, @@ -176,35 +266,191 @@ items. @item Following links to binary files (and image files on unsupported systems) causes Elpher to prompt for a filename in which to save the content. + +@item +Following links of type `h' with a selector having the `URL:' prefix, or +non-gopher URLs in text files, will result in Elpher using an external +programme to open the URL. This will be either the default system browser +or, if the @code{elpher-open-urls-with-eww} customization variable is non-nil, +Emacs' own EWW browser. (See @pxref{Customization}.) + @end itemize -Once a text, menu or query response page is retrieved, its contents are +Once a text, menu or query response page has been displayed, its contents are cached for the duration of the Emacs session. -@item @kbd{d} (@code{elpher-download}) - @item @kbd{g} (@code{elpher-go}) +Open a particular page by specifying either its URL or directly entering +a host, port and selector. + +Note that if a non-gopher protocol is used in the URL the result will be +the same as following a URL link of the same type from a gopher menu. @item @kbd{O} (@code{elpher-root-dir}) +Open the root page (empty selector) on the current host. @item @kbd{u} (@code{elpher-back}) Return to the previous page, where ``previous'' means the page where the page which was displayed immediately before the current page. @end table + +@node History and Caching, , Between-page navigation, Navigation +@section History and Caching + +The history and caching strategy in Elpher is extremely simple, but +may be confusing without a good mental model of how it works. That +is what this section attempts to provide. + +Essentially, @strong{every} time you navigate to a new page, either +by clicking or pressing @key{RET} on a link, using @key{g} to jump +to a new page by its address, or using @key{O} to open the root selector, +the following two things occur: + +@enumerate +@item +the cursor position and content for the original page are recorded in an +in-memory cache, and + +@item +the original page is set as the ``parent'' of the new page. +@end enumerate + +The only way to return to pages in this history is by using @key{u}, +which returns to the previous of the current page. +@footnote{The addition of the new page to the history happens even if +the new page is one that has been seen before. This is mostly the +desired behaviour. However, opening an explicit ``back'' link provided +by a gopher menu will also add a new entry to the history. Unless you +haven't yet visited that menu, it's therefore better to use @key{u} to +go back in this case.} + +One aspect that may seem peculiar is that Elpher lacks a corresponding ``next'' or +``forward'' command. However, since Elpher caches the position of point, +this will be automatically positioned on the link that was most recently followed +from a given page. This means that, at least for links followed from menus +and text files, the inverse of @key{u} is actually just @key{RET}. + + @node Bookmarks, Character encodings, Navigation, Top @chapter Bookmarks -@node Character encodings, Customization, Bookmarks, Top +Elpher has a very simple link bookmarking system involving the +following commands: + +@table @asis +@item @key{a} (@code{elpher-bookmark-link}) +Add a bookmark for the link at point. The minibuffer will prompt for +a name for the bookmark, which defaults to the display string. + +@item @key{A} (@code{elpher-bookmark-current}) +Add a bookmark for the current page. The minibuffer will prompt for +a name for the bookmark, defaulting to the display string associated +with the link that was followed to reach the current page. + +@item @key{x} (@code{elpher-unbookmark-link}) +Immediately remove the bookmark (if one exists) to the link at point. + +@item @key{X} (@code{elpher-unbookmark-current}) +Immediately remove the bookmark (if one exists) to the current page. + +@item @key{B} (@code{elpher-bookmarks}) +Open a page displaying all current bookmarks. Note that this bookmark +page is added to the history just as if you had opened it using a link. +Thus to return to the previous page, use @kbd{u}. This also means +that you can peruse the various bookmarks by visiting them in turn, +using @kbd{u} to return to the bookmark page (where the position of point +is cached), then moving to another bookmarked link and so on. +@end table + +Bookmarks are stored as a s-exp in the file @file{elpher-bookmarks} +in the user emacs directory (usually @file{~/.emacs.d/}). +Any command which modifies the list of bookmarks immediately updates +this file. + +@node Character encodings, Encrypted connections, Bookmarks, Top @chapter Character encodings -@node Customization, Hacking, Character encodings, Top +Responses Elpher retrieves from servers are initially read as pure +binary data. When the data is intended to be interpreted as textual (as +determined by the type parameter of the gopher menu item or the gopher +URL), this data needs to be @emph{decoded} into a sequence of +characters. To do this properly requires knowledge of the encoding +system used by whoever authored the document. + +Unfortunately gopher lacks a systematic way of acquiring this necessary +information. Thus, the details of the coding system must be either inferred from the binary data, +or must be specified by the user. + +By default, Elpher applies Emacs' built-in character encoding detection +system to the full (undecoded) response data and uses this to attempt to +convert it into a character string. +(See @pxref{Recognize coding, Recognizing coding systems, ,emacs}.) While +this approach can be okay, it is important to realise that its inference +algorithm is extremely primitive and depends heavily on assumptions based +on the language settings of your emacs system. + +The alternative is to explicitly set the coding system used for decoding +using the following command: + +@table @asis +@item @key{S} (@code{elpher-set-coding-system}) +Causes a elpher to prompt for a coding system to use for decoding +future text. The @key{TAB} key can be used at this prompt to display a +list of alternatives (which is extensive) and to autocomplete. An empty +response will cause Elpher to return to its default autodetection +behaviour. +@end table + +Note that changing the coding system only affects newly loaded text. +Thus, if text has already been decoded using an incorrect system, you +will need to select the correct coding and then reload the text using +@key{R}. + + +@node Encrypted connections, Customization, Character encodings, Top +@chapter Encrypted connections + +While RFC 1436 does not broach the topic of encryption at all, several +modern gopher servers can serve content over encrypted connections, +and a common choice for this is TLS. + +Elpher can retrieve selectors using Emacs' built-in TLS support which +uses the GnuTLS library. (It is possible to build emacs without +GnuTLS, in which case encryption is not supported.) + +To retrieve documents using TLS, Elpher's TLS mode must be enabled. +This can be directly toggled using @key{T}, but note that just as with +the character encoding, changing this mode only affects subsequent +connections. + +Alternatively, TLS mode is @emph{automatically} enabled whenever +gopher URLs starting with @code{gophers://} are followed. + +The mode is sticky, so it remains active until switched off. +It can also be automatically switched off when a TLS connection fails. +In this case Elpher will prompt for your confirmation to ensure that +you can't accidentally make a non-TLS connection. + + +@node Customization, Index, Encrypted connections, Top @chapter Customization -@node Hacking, Index, Customization, Top -@chapter Hacking -@node Index, , Hacking, Top + + +@menu +* Faces:: +* Other cutomizations:: +@end menu + +@node Faces, Other cutomizations, Customization, Customization +@section Faces + +@node Other cutomizations, , Faces, Customization +@section Other customizations + +@node Index, , Customization, Top @unnumbered Index @printindex cp