#code a.cpp
You are trying to start vscode as a super user which is not recommended. If you really want to, you must specify an alternate user data directory using the --user-data-dir argument.

#code a.cpp --user-data-dir /home/cpp
/usr/share/code/bin/../code: error while loading shared libraries: libasound.so.2: cannot open shared object file: No such file or directory

#apt search libasound 
Sorting... Done
Full Text Search... Done
libasound2/oldstable 1.1.3-5 amd64
 shared library for ALSA applications

libasound2-data/oldstable 1.1.3-5 all
 Configuration files and profiles for ALSA drivers

libasound2-dev/oldstable 1.1.3-5 amd64
 shared library for ALSA applications -- development files

libasound2-doc/oldstable 1.1.3-5 all
 documentation for user-space ALSA application programming

libasound2-plugin-equal/oldstable 0.6-7 amd64
 equalizer plugin for ALSA

libasound2-plugin-smixer/oldstable 1.1.3-5 amd64
 smixer plugin for ALSA library

libasound2-plugins/oldstable 1.1.1-1 amd64
 ALSA library additional plugins

#apt -y install libasound2
Reading package lists... Done
Building dependency tree 
Reading state information... Done
The following additional packages will be installed:
 libasound2-data
Suggested packages:
 libasound2-plugins alsa-utils
The following NEW packages will be installed:
 libasound2 libasound2-data
0 upgraded, 2 newly installed, 0 to remove and 0 not upgraded.
Need to get 669 kB of archives.
After this operation, 1981 kB of additional disk space will be used.
Get:1 http://deb.debian.org/debian stretch/main amd64 libasound2-data all 1.1.3-5 [173 kB]
Get:2 http://deb.debian.org/debian stretch/main amd64 libasound2 amd64 1.1.3-5 [497 kB]
Fetched 669 kB in 0s (3099 kB/s)
Selecting previously unselected package libasound2-data.
(Reading database ... 42374 files and directories currently installed.)
Preparing to unpack .../libasound2-data_1.1.3-5_all.deb ...
Unpacking libasound2-data (1.1.3-5) ...
Selecting previously unselected package libasound2:amd64.
Preparing to unpack .../libasound2_1.1.3-5_amd64.deb ...
Unpacking libasound2:amd64 (1.1.3-5) ...
Setting up libasound2-data (1.1.3-5) ...
Setting up libasound2:amd64 (1.1.3-5) ...
Processing triggers for libc-bin (2.24-11+deb9u4) ...

#code a.cpp --user-data-dir /home/cpp
#code --help --user-data-dir /home/cpp
Visual Studio Code 1.37.0

Usage: code [options][paths...]

To read from stdin, append '-' (e.g. 'ps aux | grep code | code -')

Options
 -d --diff <file><file> Compare two files with each other.
 -a --add <folder>Add folder(s) to the last active window.
 -g --goto <file:line[:character]>Open a file at the path on the specified line and character position.
 -n --new-window Force to open a new window.
 -r --reuse-window Force to open a file or folder in an already opened window.
 -w --wait Wait for the files to be closed before returning.
 --locale <locale>The locale to use (e.g. en-US or zh-TW).
 --user-data-dir <dir>Specifies the directory that user data is kept in. Can be used to open multiple distinct
 instances of Code.
 -v --version Print version.
 -h --help Print usage.
 --telemetry Shows all telemetry events which VS code collects.
 --folder-uri <uri>Opens a window with given folder uri(s)
 --file-uri <uri>Opens a window with given file uri(s)

Extensions Management
 --extensions-dir <dir>Set the root path for extensions.
 --list-extensions List the installed extensions.
 --show-versions Show versions of installed extensions, when using --list-extension.
 --category Filters installed extensions by provided category, when using
 --list-extension.
 --install-extension <extension-id | path-to-vsix>Installs or updates the extension. Use `--force` argument to avoid
 prompts.
 --uninstall-extension <extension-id>Uninstalls an extension.
 --enable-proposed-api <extension-id>Enables proposed API features for extensions. Can receive one or more
 extension IDs to enable individually.

Troubleshooting
 --verbose Print verbose output (implies --wait).
 --log <level>Log level to use. Default is 'info'. Allowed values are 'critical', 'error', 'warn',
 'info', 'debug', 'trace', 'off'.
 -s --status Print process usage and diagnostics information.
 --prof-startup Run CPU profiler during startup
 --disable-extensions Disable all installed extensions.
 --disable-extension <extension-id>Disable an extension.
 --inspect-extensions <port>Allow debugging and profiling of extensions. Check the developer tools for the connection
 URI.
 --inspect-brk-extensions <port>Allow debugging and profiling of extensions with the extension host being paused after
 start. Check the developer tools for the connection URI.
 --disable-gpu Disable GPU hardware acceleration.
 --max-memory Max memory size for a window (in Mbytes).