Using a private SSH key

[Vicolaships]

Hello,

I'm using VLC 3.0.2 on Kubuntu 18.04, I was previously using VLC (not sure which version) on Ubuntu 16.04

I want to open a video file via SFTP. My key is authorized on this machine, I can log-in without entering a password (after the key is unlocked).
Despite that when I open a file with VLC it asks me credentials:



Entering my credentials works fine but I want to use my SSH key, how to I do that?
I previously never have done any setup and it opened the videos without asking for credentials.

Bye

[InTheWings]

since that's using with libssh, you need the proper ssh agent environment

[Vicolaships]

My SSH agent is already configured (I have only one SSH key):

$ eval `ssh-agent`
Agent pid 3487
$ ssh-agent
SSH_AUTH_SOCK=/tmp/ssh-rJ0r3G4T5xLs/agent.3489; export SSH_AUTH_SOCK;
SSH_AGENT_PID=3490; export SSH_AGENT_PID;
echo Agent pid 3490;
$ ssh-add
Enter passphrase for /home/victor/.ssh/id_rsa:
Identity added: /home/victor/.ssh/id_rsa (/home/victor/.ssh/id_rsa)

$ dpkg -l | grep ssh
ii ksshaskpass 4:5.12.4-0ubuntu1 amd64 interactively prompt users for a passphrase for ssh-add
ii libssh-4:amd64 0.8.0~20170825.94fa1e38-1build1 amd64 tiny C SSH library (OpenSSL flavor)
ii libssh-gcrypt-4:amd64 0.8.0~20170825.94fa1e38-1build1 amd64 tiny C SSH library (gcrypt flavor)
ii libssh2-1:amd64 1.8.0-1 amd64 SSH2 client-side library
ii openssh-client 1:7.6p1-4 amd64 secure shell (SSH) client, for secure access to remote machines
ii openssh-server 1:7.6p1-4 amd64 secure shell (SSH) server, for secure access from remote machines
ii openssh-sftp-server 1:7.6p1-4 amd64 secure shell (SSH) sftp server module, for SFTP access from remote machines
ii python-paramiko 2.0.0-1ubuntu1 all Make ssh v2 connections (Python 2)
ii ssh 1:7.6p1-4 all secure shell client and server (metapackage)
ii ssh-import-id 5.7-0ubuntu1.1 all securely retrieve an SSH public key and install it locally
ii sshfs 2.8-1 amd64 filesystem client based on SSH File Transfer Protocol

Any idea of what is wrong?



Here is a full verbose log:

$ vlc -vv
VLC media player 3.0.2 Vetinari (revision 3.0.2-0-gd7b653cf14)
[000055911ca4f570] main libvlc debug: VLC media player - 3.0.2 Vetinari
[000055911ca4f570] main libvlc debug: Copyright © 1996-2018 the VideoLAN team
[000055911ca4f570] main libvlc debug: revision 3.0.2-0-gd7b653cf14
[000055911ca4f570] main libvlc debug: configured with ./configure '--build=x86_64-linux-gnu' '--prefix=/usr' '--includedir=${prefix}/include' '--mandir=${prefix}/share/man' '--infodir=${prefix}/share/info' '--sysconfdir=/etc' '--localstatedir=/var' '--disable-silent-rules' '--libdir=${prefix}/lib/x86_64-linux-gnu' '--libexecdir=${prefix}/lib/x86_64-linux-gnu' '--runstatedir=/run' '--disable-maintainer-mode' '--disable-dependency-tracking' '--config-cache' '--disable-update-check' '--enable-fast-install' '--docdir=/usr/share/doc/vlc' '--with-binary-version=3.0.2-0ubuntu0.1' '--enable-a52' '--enable-aa' '--enable-aribsub' '--enable-bluray' '--enable-avahi' '--enable-caca' '--enable-chromaprint' '--enable-chromecast' '--enable-dbus' '--enable-dca' '--enable-dvbpsi' '--enable-dvdnav' '--enable-faad' '--enable-flac' '--enable-fluidsynth' '--enable-freetype' '--enable-fribidi' '--enable-gles2' '--enable-gnutls' '--enable-harfbuzz' '--enable-jack' '--enable-kate' '--enable-libass' '--enable-libmpeg2' '--enable-libxml2' '--enable-lirc' '--enable-live555' '--enable-mad' '--enable-matroska' '--enable-mod' '--enable-mpc' '--enable-mpg123' '--enable-mtp' '--enable-ncurses' '--enable-notify' '--enable-ogg' '--enable-opus' '--enable-pulse' '--enable-qt' '--enable-realrtsp' '--enable-samplerate' '--enable-sdl-image' '--enable-sftp' '--enable-shine' '--enable-shout' '--enable-skins2' '--enable-sndio' '--enable-soxr' '--enable-speex' '--enable-svg' '--enable-svgdec' '--enable-taglib' '--enable-theora' '--enable-twolame' '--enable-upnp' '--enable-vdpau' '--enable-vnc' '--enable-vorbis' '--enable-x264' '--enable-x265' '--enable-zvbi' '--with-kde-solid=/usr/share/solid/actions/' '--disable-d3d11va' '--disable-decklink' '--disable-directx' '--disable-dsm' '--disable-dxva2' '--disable-fdkaac' '--disable-fluidlite' '--disable-freerdp' '--disable-goom' '--disable-gst-decode' '--disable-libtar' '--disable-macosx' '--disable-macosx-avfoundation' '--disable-macosx-qtkit' '--disable-mfx' '--disable-opencv' '--disable-projectm' '--disable-schroedinger' '--disable-sparkle' '--disable-srt' '--disable-telx' '--disable-vpx' '--disable-vsxu' '--disable-wasapi' '--enable-alsa' '--enable-dc1394' '--enable-dv1394' '--enable-libplacebo' '--enable-linsys' '--enable-nfs' '--enable-omxil' '--enable-udev' '--enable-v4l2' '--enable-wayland' '--enable-libva' '--enable-vcd' '--enable-smbclient' '--disable-oss' '--enable-crystalhd' '--enable-mmx' '--enable-sse' '--disable-neon' '--disable-altivec' 'build_alias=x86_64-linux-gnu' 'CFLAGS=-g -O2 -fdebug-prefix-map=/build/vlc-RT1iKM/vlc-3.0.2=. -fstack-protector-strong -Wformat -Werror=format-security ' 'LDFLAGS=-Wl,-Bsymbolic-functions -Wl,-z,relro -Wl,-z,now -Wl,--as-needed' 'CPPFLAGS=-Wdate-time -D_FORTIFY_SOURCE=2' 'CXXFLAGS=-g -O2 -fdebug-prefix-map=/build/vlc-RT1iKM/vlc-3.0.2=. -fstack-protector-strong -Wformat -Werror=format-security ' 'OBJCFLAGS=-g -O2 -fdebug-prefix-map=/build/vlc-RT1iKM/vlc-3.0.2=. -fstack-protector-strong -Wformat -Werror=format-security'
[000055911ca4f570] main libvlc debug: searching plug-in modules
[000055911ca4f570] main libvlc debug: loading plugins cache file /usr/lib/x86_64-linux-gnu/vlc/plugins/plugins.dat
[000055911ca4f570] main libvlc debug: recursively browsing `/usr/lib/x86_64-linux-gnu/vlc/plugins'
[000055911ca4f570] main libvlc debug: plug-ins loaded: 518 modules
[000055911ca4f570] main libvlc debug: opening config file (/home/victor/.config/vlc/vlcrc)
[000055911ca4f8c0] main logger debug: looking for logger module matching "any": 4 candidates
[000055911ca4f8c0] main logger debug: using logger module "console"
[000055911ca4f570] main libvlc debug: translation test: code is "fr"
[000055911cae4c20] main keystore debug: looking for keystore module matching "memory": 4 candidates
[000055911cae4c20] main keystore debug: using keystore module "memory"
[000055911ca4f570] main libvlc debug: CPU has capabilities MMX MMXEXT SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 AVX AVX2 FPU
[000055911caf3440] main input debug: Creating an input for 'Médiathèque'
[000055911caf3440] main input debug: Input is a meta file: disabling unneeded options
[000055911caf3440] main input debug: using timeshift granularity of 50 MiB
[000055911caf3440] main input debug: using default timeshift path
[000055911caf3440] main input debug: `file/directory:///home/victor/.local/share/vlc/ml.xspf' gives access `file' demux `directory' path `/home/victor/.local/share/vlc/ml.xspf'
[000055911cae4fc0] main input source debug: creating demux: access='file' demux='directory' location='/home/victor/.local/share/vlc/ml.xspf' file='/home/victor/.local/share/vlc/ml.xspf'
[000055911cae5170] main demux debug: looking for access_demux module matching "file": 17 candidates
[000055911cae5170] main demux debug: no access_demux modules matched
[000055911cb008b0] main stream debug: creating access: file:///home/victor/.local/share/vlc/ml.xspf
[000055911cb008b0] main stream debug: (path: /home/victor/.local/share/vlc/ml.xspf)
[000055911cb008b0] main stream debug: looking for access module matching "file": 28 candidates
[000055911cb008b0] main stream debug: using access module "filesystem"
[000055911cb01900] main stream debug: looking for stream_filter module matching "prefetch,cache_read": 26 candidates
[000055911cb01900] cache_read stream debug: Using stream method for AStream*
[000055911cb01900] cache_read stream debug: starting pre-buffering
[000055911cb01900] cache_read stream debug: received first data after 0 ms
[000055911cb01900] cache_read stream debug: pre-buffering done 296 bytes in 0s - 15213 KiB/s
[000055911cb01900] main stream debug: using stream_filter module "cache_read"
[000055911cb029a0] main stream debug: looking for stream_filter module matching "any": 26 candidates
[000055911cb029a0] playlist stream debug: using XSPF playlist reader
[000055911cb029a0] main stream debug: using stream_filter module "playlist"
[000055911cb029a0] main stream debug: stream filter added to 0x55911cb01900
[000055911cb05ed0] main stream debug: looking for stream_filter module matching "any": 26 candidates
[000055911cb05ed0] main stream debug: no stream_filter modules matched
[000055911cae2030] main stream_directory debug: looking for stream_directory module matching "any": 1 candidates
[000055911cae2030] main stream_directory debug: no stream_directory modules matched
[000055911cae4fc0] main input source debug: attachment of directory-extractor failed for file:///home/victor/.local/share/vlc/ml.xspf
[000055911cb05ed0] main stream debug: looking for stream_filter module matching "record": 26 candidates
[000055911cb05ed0] main stream debug: using stream_filter module "record"
[000055911cae4fc0] main input source debug: creating demux: access='file' demux='directory' location='/home/victor/.local/share/vlc/ml.xspf' file='/home/victor/.local/share/vlc/ml.xspf'
[000055911cae5170] main demux debug: looking for demux module matching "directory": 55 candidates
[000055911cae5170] main demux debug: using demux module "directory"
[000055911cb1c640] main demux meta debug: looking for meta reader module matching "any": 2 candidates
[000055911cb1c640] lua demux meta debug: Trying Lua scripts in /home/victor/.local/share/vlc/lua/meta/reader
[000055911cb1c640] lua demux meta debug: Trying Lua scripts in /usr/lib/x86_64-linux-gnu/vlc/lua/meta/reader
[000055911cb1c640] lua demux meta debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/meta/reader/filename.luac
[000055911cb1c640] lua demux meta debug: Trying Lua scripts in /usr/share/vlc/lua/meta/reader
[000055911cb1c640] main demux meta debug: no meta reader modules matched
[000055911caf3440] main input debug: `file/directory:///home/victor/.local/share/vlc/ml.xspf' successfully opened
[000055911cb212a0] main xml reader debug: looking for xml reader module matching "any": 1 candidates
[000055911cb212a0] main xml reader debug: using xml reader module "xml"
[000055911caf3440] main input debug: EOF reached
[000055911cae5170] main demux debug: removing module "directory"
[000055911cb05ed0] main stream debug: removing module "record"
[000055911cb029a0] main stream debug: removing module "playlist"
[000055911cb01900] main stream debug: removing module "cache_read"
[000055911cb008b0] main stream debug: removing module "filesystem"
[000055911ca534e0] main playlist debug: creating audio output
[000055911cb05a10] main audio output debug: looking for audio output module matching "any": 6 candidates
[000055911cb05a10] vlcpulse audio output debug: using library version 11.1.0
[000055911cb05a10] vlcpulse audio output debug: (compiled with version 11.1.0, protocol 32)
[000055911cb05a10] vlcpulse audio output debug: connected locally to unix:/run/user/1000/pulse/native as client #14
[000055911cb05a10] vlcpulse audio output debug: using protocol 32, server protocol 32
[000055911cb05a10] pulse audio output debug: adding sink 0: alsa_output.pci-0000_00_1b.0.analog-stereo (Audio interne Stéréo analogique)
[000055911cb05a10] main audio output debug: using audio output module "pulse"
[000055911ca534e0] main playlist debug: keeping audio output
[000055911cb2eb10] main interface debug: looking for interface module matching "dbus,none": 19 candidates
[000055911cb2eb10] dbus interface debug: listening on dbus as: org.mpris.MediaPlayer2.vlc
[000055911cb2eb10] main interface debug: using interface module "dbus"
[000055911cb32d50] main interface debug: looking for interface module matching "hotkeys,none": 19 candidates
[000055911cb32d50] main interface debug: using interface module "hotkeys"
[000055911cb33840] main interface debug: looking for interface module matching "globalhotkeys,none": 19 candidates
[000055911cb2eb10] dbus interface debug: Getting property Identity
[000055911cb2eb10] dbus interface debug: Getting All properties
[000055911cb2eb10] dbus interface debug: Getting All properties
[000055911cb33840] main interface debug: using interface module "xcb_hotkeys"
[000055911ca4f570] main libvlc: Lancement de vlc avec l'interface par défaut. Utilisez « cvlc » pour démarrer VLC sans interface.
[000055911cb34dd0] main interface debug: looking for interface module matching "any": 19 candidates
[00007f925c196620] main generic debug: looking for extension module matching "any": 1 candidates
[00007f925c196620] lua generic debug: Opening Lua Extension module
[00007f925c196620] lua generic debug: Trying Lua scripts in /home/victor/.local/share/vlc/lua/extensions
[00007f925c196620] lua generic debug: Trying Lua scripts in /usr/lib/x86_64-linux-gnu/vlc/lua/extensions
[00007f925c196620] lua generic debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/extensions/VLSub.luac
[00007f925c196620] lua generic debug: Scanning Lua script /usr/lib/x86_64-linux-gnu/vlc/lua/extensions/VLSub.luac
[00007f925c196620] lua generic debug: Script /usr/lib/x86_64-linux-gnu/vlc/lua/extensions/VLSub.luac has the following capability flags: 0x5
[00007f925c196620] lua generic debug: Trying Lua scripts in /usr/share/vlc/lua/extensions
[00007f925c196620] main generic debug: using extension module "lua"
[000055911cb34dd0] main interface debug: using interface module "qt"
[000055911ca534e0] main playlist: playlist is empty
[000055911ca534e0] main playlist debug: nothing to play
[000055911cb2eb10] dbus interface debug: Getting property Metadata
[000055911cb2eb10] dbus interface debug: Getting property Position
[000055911cb2eb10] dbus interface debug: Getting property PlaybackStatus
[000055911cb2eb10] dbus interface debug: Getting property CanPause
[000055911cb2eb10] dbus interface debug: Getting property CanPlay
[000055911cb2eb10] dbus interface debug: Getting property CanGoNext
[000055911cb2eb10] dbus interface debug: Getting property CanGoPrevious
[000055911cb2eb10] dbus interface debug: Getting property CanSeek
[000055911cb2eb10] dbus interface debug: Getting property Volume
[000055911ca534e0] main playlist debug: processing request item: Apricot.mp4, node: Liste de lecture, skip: 0
[000055911ca534e0] main playlist debug: rebuilding array of current - root Liste de lecture
[000055911ca534e0] main playlist debug: rebuild done - 1 items, index 0
[000055911ca534e0] main playlist debug: starting playback of new item
[000055911ca534e0] main playlist debug: resyncing on Apricot.mp4
[000055911ca534e0] main playlist debug: Apricot.mp4 is at 0
[000055911ca534e0] main playlist debug: creating new input thread
[00007f922c000c40] main input debug: Creating an input for 'Apricot.mp4'
[000055911ca534e0] main playlist debug: requesting art for new input thread
[00007f922c000c40] main input debug: using timeshift granularity of 50 MiB
[00007f922c000c40] main input debug: using default timeshift path
[00007f922c000c40] main input debug: `sftp://webserver/home/victor/hdd/Apricot.mp4' gives access `sftp' demux `any' path `webserver/home/victor/hdd/Apricot.mp4'
[00007f9230000f60] main input source debug: creating demux: access='sftp' demux='any' location='webserver/home/victor/hdd/Apricot.mp4' file='(null)'
[00007f9230001130] main demux debug: looking for access_demux module matching "sftp": 17 candidates
[00007f9230001130] main demux debug: no access_demux modules matched
[00007f9230001620] main stream debug: creating access: sftp://webserver/home/victor/hdd/Apricot.mp4
[00007f9230001620] main stream debug: looking for access module matching "sftp": 28 candidates
[00007f9228000be0] main meta fetcher debug: looking for meta fetcher module matching "any": 1 candidates
[00007f9228000be0] lua meta fetcher debug: Trying Lua scripts in /home/victor/.local/share/vlc/lua/meta/fetcher
[00007f9228000be0] lua meta fetcher debug: Trying Lua scripts in /usr/lib/x86_64-linux-gnu/vlc/lua/meta/fetcher
[000055911cb2eb10] dbus interface debug: Getting All properties
[00007f9228000be0] lua meta fetcher debug: Trying Lua scripts in /usr/share/vlc/lua/meta/fetcher
[00007f9228000be0] main meta fetcher debug: no meta fetcher modules matched
[00007f9228000be0] main art finder debug: looking for art finder module matching "any": 2 candidates
[000055911cb2eb10] dbus interface debug: Getting All properties
[000055911cb2eb10] dbus interface debug: Getting property CanSeek
[000055911cb2eb10] dbus interface debug: Getting property Position
[000055911cb34dd0] qt interface debug: IM: Setting an input
[000055911cb2eb10] dbus interface debug: Getting property Position
[00007f9230001620] main stream debug: net: connecting to webserver port 22
[00007f9230001620] main stream debug: connection succeeded (socket = 32)
[00007f9228000be0] lua art finder debug: Trying Lua scripts in /home/victor/.local/share/vlc/lua/meta/art
[00007f9228000be0] lua art finder debug: Trying Lua scripts in /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art
[00007f9228000be0] lua art finder debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/00_musicbrainz.luac
[00007f9228000be0] lua art finder debug: skipping script (unmatched scope) /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/00_musicbrainz.luac
[00007f9228000be0] lua art finder debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/01_googleimage.luac
[00007f9228000be0] lua art finder debug: skipping script (unmatched scope) /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/01_googleimage.luac
[00007f9228000be0] lua art finder debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/02_frenchtv.luac
[00007f9228000be0] lua art finder debug: skipping script (unmatched scope) /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/02_frenchtv.luac
[00007f9228000be0] lua art finder debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/03_lastfm.luac
[00007f9228000be0] lua art finder debug: skipping script (unmatched scope) /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/03_lastfm.luac
[00007f9228000be0] lua art finder debug: Trying Lua scripts in /usr/share/vlc/lua/meta/art
[00007f9228000be0] main art finder debug: no art finder modules matched
[00007f921c000c70] main meta fetcher debug: looking for meta fetcher module matching "any": 1 candidates
[00007f921c000c70] lua meta fetcher debug: Trying Lua scripts in /home/victor/.local/share/vlc/lua/meta/fetcher
[00007f921c000c70] lua meta fetcher debug: Trying Lua scripts in /usr/lib/x86_64-linux-gnu/vlc/lua/meta/fetcher
[00007f921c000c70] lua meta fetcher debug: Trying Lua scripts in /usr/share/vlc/lua/meta/fetcher
[00007f921c000c70] main meta fetcher debug: no meta fetcher modules matched
[00007f921c000c70] main art finder debug: looking for art finder module matching "any": 2 candidates
[00007f921c000c70] lua art finder debug: Trying Lua scripts in /home/victor/.local/share/vlc/lua/meta/art
[00007f921c000c70] lua art finder debug: Trying Lua scripts in /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art
[00007f921c000c70] lua art finder debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/00_musicbrainz.luac
[00007f921c000c70] lua art finder debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/01_googleimage.luac
[00007f921c000c70] lua art finder debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/02_frenchtv.luac
[00007f921c000c70] lua art finder debug: Trying Lua playlist script /usr/lib/x86_64-linux-gnu/vlc/lua/meta/art/03_lastfm.luac
[00007f921c000c70] lua art finder debug: Trying Lua scripts in /usr/share/vlc/lua/meta/art
[00007f921c000c70] main art finder debug: no art finder modules matched
uint DBusMenuExporterDBus::GetLayout(int, int, const QStringList&, DBusMenuLayoutItem&): Condition failed: menu
[000055911cb2eb10] dbus interface debug: Getting property CanSeek
[000055911cb2eb10] dbus interface debug: Getting property Position
[00007f9230001620] sftp stream debug: Unable to check the remote host
[00007f9230010f00] main keystore debug: looking for keystore module matching "any": 4 candidates
[00007f9230010f00] main keystore debug: using keystore module "kwallet"
[00007f9230001620] sftp stream error: Unable to initialize the SFTP session
[00007f9230010f00] main keystore debug: removing module "kwallet"
[00007f9230001620] main stream debug: no access modules matched
[000055911ca534e0] main playlist debug: dead input
[000055911ca534e0] main playlist debug: changing item without a request (current 0/1)
[000055911ca534e0] main playlist debug: nothing to play
[000055911cb2eb10] dbus interface debug: Getting property CanSeek
[000055911cb34dd0] qt interface debug: IM: Deleting the input
[000055911cb2eb10] dbus interface debug: Getting property Position
uint DBusMenuExporterDBus::GetLayout(int, int, const QStringList&, DBusMenuLayoutItem&): Condition failed: menu
uint DBusMenuExporterDBus::GetLayout(int, int, const QStringList&, DBusMenuLayoutItem&): Condition failed: menu
[000055911cb2eb10] dbus interface debug: Getting property CanSeek
[000055911ca4f570] main libvlc debug: exiting
[000055911ca4f570] main libvlc debug: exiting
[000055911ca4f570] main libvlc debug: removing all interfaces
[000055911cb34dd0] main interface debug: removing module "qt"
[000055911ca534e0] main playlist debug: deactivating the playlist
[000055911cb05a10] main audio output debug: removing module "pulse"
[000055911cb34dd0] qt interface debug: requesting exit...
[000055911cb34dd0] qt interface debug: waiting for UI thread...
[000055911cb34dd0] qt interface debug: QApp exec() finished
[000055911cb34dd0] qt interface debug: Video is not needed anymore
[000055911cb34dd0] qt interface debug: Killing extension dialog provider
[000055911cb34dd0] qt interface debug: ExtensionsDialogProvider is quitting...
[00007f925c196620] main generic debug: removing module "lua"
[000055911cb33840] main interface debug: removing module "xcb_hotkeys"
[000055911cb32d50] main interface debug: removing module "hotkeys"
[000055911cb2eb10] main interface debug: removing module "dbus"
[000055911ca534e0] main playlist debug: destroying
[000055911cb30200] main playlist export debug: saving media library to file /home/victor/.local/share/vlc/ml.xspf.tmp3794
[000055911cb30200] main playlist export debug: looking for playlist export module matching "export-xspf": 4 candidates
[000055911cb30200] main playlist export debug: using playlist export module "export"
[000055911cb30200] main playlist export debug: removing module "export"
[000055911ca534e0] main playlist debug: deleting item `Médiathèque'
[000055911ca534e0] main playlist debug: deleting item `Apricot.mp4'
[000055911ca534e0] main playlist debug: deleting item `Liste de lecture'
[000055911cae4c20] main keystore debug: removing module "memory"
QObject::~QObject: Timers cannot be stopped from another thread

[InTheWings]

There's no issue.
You need to add username in the mrl.

sftp://user@

[kilovar40]

There's no issue.
You need to add username in the mrl.

sftp://user@

What is the correct syntax to specify a private key file in the command line? I am on windows and using putty with private keys to access the remote machine.

[Vicolaships]

There's no issue.
You need to add username in the mrl.

sftp://user@

It works fine with something like: sftp://victor@webserver/home/victor/hdd/Apricot.mp4

I'll try to understand why Dolphin doesn't format the MRL that way when I click open on a file!

EDIT:

In dolphin I added a Dolphin favorite for the distant machine as sftp://webserver/home/victor, this works fine because both users (local/remote) are named victor, but VLC doesn't use the default key in that case. I have modified my Dolphin favorite to sftp://victor@webserver/home/victor and VLC now doesn't ask the credentials because it uses the key.

Problem solved!