Enhance dotenv run: Switch to execvpe for better resource management …

…and signal handling

src/dotenv/cli.py

@@ -3,7 +3,6 @@
 import shlex
 import sys
 from contextlib import contextmanager
-from subprocess import Popen
 from typing import Any, Dict, IO, Iterator, List
 
 try:
@@ -161,14 +160,13 @@ def run(ctx: click.Context, override: bool, commandline: List[str]) -> None:
     if not commandline:
         click.echo('No command given.')
         exit(1)
-    ret = run_command(commandline, dotenv_as_dict)
-    exit(ret)
+    run_command(commandline, dotenv_as_dict)
 
 
-def run_command(command: List[str], env: Dict[str, str]) -> int:
-    """Run command in sub process.
+def run_command(command: List[str], env: Dict[str, str]) -> None:
+    """Replace the current process with the specified command.
 
-    Runs the command in a sub process with the variables from `env`
+    Replaces the current process with the specified command and the variables from `env`
     added in the current environment variables.
 
     Parameters
@@ -180,20 +178,13 @@ def run_command(command: List[str], env: Dict[str, str]) -> int:
 
     Returns
     -------
-    int
-        The return code of the command
+    None
+        This function does not return any value. It replaces the current process with the new one.
 
     """
     # copy the current environment variables and add the vales from
     # `env`
     cmd_env = os.environ.copy()
     cmd_env.update(env)
 
-    p = Popen(command,
-              universal_newlines=True,
-              bufsize=0,
-              shell=False,
-              env=cmd_env)
-    _, _ = p.communicate()
-
-    return p.returncode
+    os.execvpe(command[0], args=command, env=cmd_env)