SUBPROCESS_RUN run process

with optional cwd, env. vars, stdin, timeout

handles command lines with spaces input each segment of the command as an element in a string array this is how python subprocess.run works

Inputs
Outputs
Example
Gfortran streams

Inputs

cmd: command line. Windows paths should use filesep '\'
opt.env: environment variable struct to set
opt.cwd: working directory to use while running command
opt.stdin: string to pass to subprocess stdin pipe
opt.stdout: logical to indicate whether to use pipe for stdout
opt.stderr: logical to indicate whether to use pipe for stderr

Outputs

status: 0 is generally success. Other codes as per the program / command run
msg: combined stdout and stderr from process

Example

subprocess_run('mpiexec -help2'); subprocess_run('sh -c "ls -l"'); subprocess_run('cmd /c "dir /Q /L"');

NOTE: if cwd option used, any paths must be absolute, or they are relative to pwd.

function [status, msg] = subprocess_run(cmd, opt)

arguments
  cmd (1,:) string
  opt.env struct {mustBeScalarOrEmpty} = struct.empty
  opt.cwd {mustBeTextScalar} = ''
  opt.stdin {mustBeTextScalar} = ''
  opt.stdout (1,1) logical = true
  opt.stderr (1,1) logical = true
  opt.echo (1,1) logical = false
end


if ~strempty(opt.cwd)
  mustBeFolder(opt.cwd)
  cmd = join(["cd", opt.cwd, "&&", cmd]);
end

if ~strempty(opt.stdin)
  cmd = join(["echo", opt.stdin, "|", cmd]);
end


if ~opt.stderr
  if ispc
    cmd = join([cmd, "2> nul"]);
  else
    cmd = join([cmd, "2> /dev/null"]);
  end
end

if ~opt.stdout
  if ispc
    cmd = join([cmd, "> nul"]);
  else
    cmd = join([cmd, "> /dev/null"]);
  end
end

% deal struct into name, value pairs for system()
if isempty(opt.env)
  env_pairs = {};
else
  f = fieldnames(opt.env);
  env_pairs = cell(1, 2 * numel(f));
  for i = 1:numel(f)
    env_pairs{2*i-1} = f{i};
    env_pairs{2*i} = opt.env.(f{i});
  end
end

Gfortran streams

https://www.mathworks.com/matlabcentral/answers/91919-why-does-the-output-of-my-fortran-script-not-show-up-in-the-matlab-command-window-when-i-execute-it#answer_101270 Matlab grabs the stdout, stderr, stdin handles of a Gfortran program, even when it's using Java. We must disable this behavior for the duration the running process.

outold = getenv("GFORTRAN_STDOUT_UNIT");
setenv("GFORTRAN_STDOUT_UNIT", "6");
errold = getenv("GFORTRAN_STDERR_UNIT");
setenv("GFORTRAN_STDERR_UNIT", "0");
inold = getenv("GFORTRAN_STDIN_UNIT");
setenv("GFORTRAN_STDIN_UNIT", "5");

if opt.echo
  disp(cmd)
end

[status, msg] = system(join(cmd), env_pairs{:});

setenv("GFORTRAN_STDOUT_UNIT", outold);
setenv("GFORTRAN_STDERR_UNIT", errold);
setenv("GFORTRAN_STDIN_UNIT", inold);


msg = strtrim(msg);

end


%!testif 0

SUBPROCESS_RUN run process

Contents

Inputs

Outputs

Example

Gfortran streams