usage.txt

  --open | -o             Automatically open after finishing
                          
                          Default: false

  --on-port | -P          Run a given command and then generate
                          the flamegraph. The command as specified
                          has access to a $PORT variable. 
                          The $PORT variable is set according
                          to the first port that profiled process 
                          opens. 

                          Example: 
                          0x -P 'autocannon localhost:$PORT' app.js

                          Note: Remember to use single quotes or else
                          escape the $PORT variable.

                          Default: ''


  -q | --quiet            Only output flamegraph URI, and fatal errors.
                          
                          Default: false

  -s | --silent           Complete silence, 0x will not output anything,
                          other than fatal errors.
                          
                          Default: false

  --kernel-tracing        Use an OS kernel tracing tool (perf on Linux or 
                          dtrace on macOs and Solaris). This will capture 
                          native stack frames (C++ modules and Libuv I/O), 
                          but may result in missing stacks on Node 8.
                          
                          Default: false



  --output-dir | -D       Specify artifact output directory.
                          Template variables {outputDir}, {pid}, {timestamp}, {cwd}
                          (current working directory) and {name} 
                          (based on the --name flag) are supported.

                          Default: '{pid}.0x'

  --output-html | -F      Specify destination path for the flamegraph HTML file.
                          Template variables {outputDir}, {pid}, {timestamp}, {cwd}
                          (current working directory) and {name} 
                          (based on the --name flag) are supported. 
                          May also be set to - to send HTML file to STDOUT (note
                          due to the nature of CLI argument parsing, this must be 
                          set using =, e.g. --output-html=-).

                          If either this flag or --name is set to - then the HTML 
                          will go to STDOUT. 
                           
                          Default: '{outputDir}/{name}.html'

  --kernel-tracing-debug  Show output from dtrace or perf tools. 
                          
                          Default: false

  --tree-debug            Output a JSON file of stacks as {outputDir}/stacks.{pid}.json
                          
                          Default: false

  --collect-only          Do not process captured stacks into a flamegraph.

  --collect-delay         Specify a delay(ms) before collecting data.


  --visualize-only <dir>  Build or rebuild flamegraph using the output dir.
                          Counterpart to --collect-only.

  --name                  The name of the HTML file, without the .html extension
                          Can be set to - to write HTML to STDOUT (note
                          due to the nature of CLI argument parsing, this must 
                          be set using =, e.g. --name=-)

                          If either this flag or --output-html is set to - 
                          then the HTML will go to STDOUT.

                          Default: flamegraph

  --title                 Set the title to display in the flamegraph UI
                          
                          Default: node [nodeFlags] script.js

  -v | --version          Output the 0x version