subprocess_run: use string internally for expediency

Author: scivision

+stdlib/subprocess_run.m

@@ -27,38 +27,37 @@
 
 function [status, msg] = subprocess_run(cmd, opt)
 arguments
-  cmd {mustBeTextScalar}
+  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
 end
 
-cmd = char(cmd);
 
 if ~strempty(opt.cwd)
-  cmd = strjoin({'cd', char(opt.cwd), '&&', cmd});
+  cmd = join(["cd", opt.cwd, "&&", cmd]);
 end
 
 if ~strempty(opt.stdin)
-  cmd = strjoin({'echo', char(opt.stdin), '|', cmd});
+  cmd = join(["echo", opt.stdin, "|", cmd]);
 end
 
 
 if ~opt.stderr
   if ispc
-    cmd = strjoin({cmd, '2> nul'});
+    cmd = join([cmd, "2> nul"]);
   else
-    cmd = strjoin({cmd, '2> /dev/null'});
+    cmd = join([cmd, "2> /dev/null"]);
   end
 end
 
 if ~opt.stdout
   if ispc
-    cmd = strjoin({cmd, '> nul'});
+    cmd = join([cmd, "> nul"]);
   else
-    cmd = strjoin({cmd, '> /dev/null'});
+    cmd = join([cmd, "> /dev/null"]);
   end
 end
 
@@ -86,7 +85,7 @@
 inold = getenv("GFORTRAN_STDIN_UNIT");
 setenv("GFORTRAN_STDIN_UNIT", "5");
 
-[status, msg] = system(cmd, env_pairs{:});
+[status, msg] = system(join(cmd), env_pairs{:});
 
 setenv("GFORTRAN_STDOUT_UNIT", outold);
 setenv("GFORTRAN_STDERR_UNIT", errold);