Files transferred over shell protocol

<h2 id="protocol-messages">Protocol messages</h2>
<p>Client sends text requests of the following form:
</p>
#FISH_COMMAND arguments...
equivalent shell commands,
which may be multi-line

<p>Fish commands are all defined, shell equivalents may vary.
Fish commands always have priority: the server is expected to execute a fish command if it understands it. If it does not, however, it can try to execute a shell command.
When there is no special server program, Unix shell ignores the fish command as a comment and executes the equivalent shell command(s).
</p><p>Server replies are multi-line, but always end with
</p>
### xyz<optional text>

<p>line. ### is a prefix to mark this line, xyz is the return code.
Return codes are a superset to those used in <a href="/facts/FTP/THuWgzfw">FTP</a>.
The codes 000 and 001 are special, their meaning depends on presence of server output before the end line.
</p>
<h2 id="session-initiation">Session initiation</h2>
<p>The client initiates SSH or RSH connection with echo FISH:;/bin/sh as the command executed on remote machine. This should make it possible for the server to distinguish FISH connections from normal RSH or SSH.
</p><p>The first two commands sent to the server are FISH and VER to negotiate FISH protocol, its version and extensions.
</p>
 #FISH
 echo; start_fish_server; echo '### 200'

#VER 0.0.2 <feature1> <feature2> <...>
 echo '### 000'

<p>The server may reply to VER command with a lines like
</p>
VER 0.0.0 <feature2> <...>
### 200

<p>which indicates supported version of the FISH protocol and supported extensions.
</p>
<h2 id="implementations">Implementations</h2>
<ul><li><a href="/facts/Midnight_Commander/RxslvJD4">Midnight Commander</a><a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a></li>
<li><a href="/facts/Far_Manager/oowTjWe4">far2l</a><a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a></li>
<li><a href="/facts/Lftp/PFagWSBJ">Lftp</a><a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a></li>
<li>fish:// <a href="/facts/KDE/PCh32IWA">KDE</a> <a href="/facts/KIO/hstkuzC5">kioslave</a><a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> (with <a href="/facts/Konqueror/qWCwNfur">konqueror</a>, <a href="/facts/Krusader/4Y5hySMs">Krusader</a> or <a href="/facts/Dolphin_(file_manager)/dlFn7brb">Dolphin</a>)</li>
<li>fish as <a href="https://github.com/greyltc/tcl-vfs/blob/master/library/template/fishvfs.tcl">tcl-vfs</a></li>
<li>FISH was implemented in <a href="/facts/Emacs/BvGxuAxQ">Emacs</a> TRAMP some time ago, but support was removed<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a><a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> (although TRAMP still can use shell connections in a similar way using tramp-sh.el script file)</li></ul>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/SSHFS/8R1zuVvR">SSHFS</a></li>
<li><a href="/facts/SSH_File_Transfer_Protocol/88YptbER">SSH File Transfer Protocol</a></li></ul>

<h2 id="external-links">External links</h2>
<ul><li><a href="http://cvs.savannah.gnu.org/viewcvs/mc/mc/vfs/README.fish?view=markup">README.fish from Midnight Commander</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>File: Fish.c - via Midnight Commander Official Repository <a href="https://github.com/MidnightCommander/mc/blob/master/src/vfs/fish/fish.c" target="_blank">https://github.com/MidnightCommander/mc/blob/master/src/vfs/fish/fish.c</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>"Mc/Fish.c at master · MidnightCommander/Mc". GitHub. <a href="https://github.com/MidnightCommander/mc/blob/master/src/vfs/fish/fish.c" target="_blank">https://github.com/MidnightCommander/mc/blob/master/src/vfs/fish/fish.c</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>"Feature: Consider porting FISH(FIle transfer over SHell filesystem) from Midnight Commander · Issue #1819 · elfmz/Far2l". GitHub. <a href="https://github.com/elfmz/far2l/issues/1819" target="_blank">https://github.com/elfmz/far2l/issues/1819</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
<li id="fn:4"><p>"LFTP/SRC/Fish.cc at master · lavv17/LFTP". GitHub. <a href="https://github.com/lavv17/lftp/blob/master/src/Fish.cc" target="_blank">https://github.com/lavv17/lftp/blob/master/src/Fish.cc</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li>
<li id="fn:5"><p>"Kio-extras/Fish/Fish.CPP at master · KDE/Kio-extras". GitHub. <a href="https://github.com/KDE/kio-extras/blob/master/fish/fish.cpp" target="_blank">https://github.com/KDE/kio-extras/blob/master/fish/fish.cpp</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li>
<li id="fn:6"><p>related commit in Emacs <a href="https://github.com/emacs-mirror/emacs/commit/03c1ad4351c10ec998410e8d34f52ac4a1a0decd#diff-96ee1cf8a36451f16ddf3f468f6ac74643eeee171d17054ca0c8cbf6653a26a8" target="_blank">https://github.com/emacs-mirror/emacs/commit/03c1ad4351c10ec998410e8d34f52ac4a1a0decd#diff-96ee1cf8a36451f16ddf3f468f6ac74643eeee171d17054ca0c8cbf6653a26a8</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li>
<li id="fn:7"><p>"Re: Tramp's fish method". <a href="https://lists.gnu.org/archive/html/tramp-devel/2010-09/msg00001.html" target="_blank">https://lists.gnu.org/archive/html/tramp-devel/2010-09/msg00001.html</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li>
</ol>

Files transferred over shell protocol open-in-new

Files transferred over shell protocol