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Describe the bug

I can't get the expected output of some system commands whose output I want to reuse after executing them in a V program.

I'm running into this when using os.execute or using an os.Process.

Reproduction Steps

• V on Windows

  // main.v
  import os
  
  println(os.execute('fc /lnwt mod.txt mod2.txt').output) // Prints a blank line.
  // os.system('fc /lnwt mod.txt mod2.txt') // Results in the correct output in the terminal.
  

• python example

  # main.py
  import subprocess
  
  def run_fc(file1, file2):
     cmd = f'fc /lnwt {file1} {file2}'
     result = subprocess.run(cmd, stderr=subprocess.STDOUT, stdout=subprocess.PIPE)
     return result.stdout.decode()
  
  output = run_fc('mod.txt', 'mod2.txt')
  print(output) # Prints the expected output.
  

• other V example (not limited to windows):

  println(os.execute('${@VEXE} -prod run ${@VEXEROOT}/examples/hello_world.v').output)
  /*
  ❯ v run main.v
  Hello, World!
  
  */
  
  os.system('${@VEXE} -prod run ${@VEXEROOT}/examples/hello_world.v')
  /*
  ❯ v run main.v
  Note: building an optimized binary takes much longer. It shouldn't be used with `v run`.
  Use `v run` without optimization, or build an optimized binary with -prod first, then run it separately.
  Hello, World!
  */
  

Expected Behavior

Full std_output and std_error in output

Current Behavior

No or limited string in output.

Possible Solution

No response

Additional Information/Context

No response

V version

weekly.2024.18.2

Environment details (OS name and version, etc.)

x64 linux, windows 11 VM

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Try reverting c7fb755 locally, to see if that will help?

It is a recent change to os.execute .

Although c7fb755 was in vlib/os/os_nix.c.v, and you are reporting it for windows 🤔 . Perhaps we should investigate the vlib/os/os_windows.c.v version more instead.

Does os.raw_execute work?

Thanks for looking into it @spytheman.

Can't get it working when reverting.

raw_execute doesn't work either. execute is very close to raw_execute on windows

https://github.com/vlang/v/blob/58527cc71c49d8d77d99ddf06a26dab0e1ae00bf/vlib/os/os_windows.c.v#L289-L297