Bug #8550: On Windows Process.spawn 'command', 'arg1', 'arg2', ... evals the arguments

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 2.0.0p195 (2013-05-14) [x64-mingw32]
• Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN

[mdesantis (Maurizio De Santis)]

=begin
Environment: ruby 2.0.0p195 (2013-05-14) [x64-mingw32] (RubyInstaller with DevKit) on Windows 7 64bit

According to the Process.spawn documentation, the syntax 'cmdname, arg1, ...' doesn't involve the shell. Indeed, on Unix this is true: ((%Process.spawn 'echo', '$PATH'%)) prints '$PATH'.

But on Windows the behaviour is different: executing ((%Process.spawn 'echo', '%Path%'%)) prints the contents of the Path environment variable.

I think the behaviour should be the same on the different OSes; at least, if it is not possible, the documentation should point it out.
=end

[luislavena (Luis Lavena)]

Hello,

On Windows, 'echo' is not an external command, is part of cmd.exe internal commands, like cd and others.

[nobu (Nobuyoshi Nakada)]

• Category set to doc

This is a spec.
Otherwise you have to write system(ENV["COMSPEC"], "/c", "echo foo"), and it seems too messy.

Patches for the rdoc are welcome.

[steveklabnik (Steve Klabnik)]

• File 0001-Add-caveats-to-Process-spawn-regarding-shell-built-i.patch 0001-Add-caveats-to-Process-spawn-regarding-shell-built-i.patch added

I've attached a patch for the RDOC, what do you think?

[zzak (zzak _)]

• Status changed from Open to Closed
• % Done changed from 0 to 100

This issue was solved with changeset r42391.
Maurizio, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

• process.c: [DOC] Document caveats of command form of Process.spawn
  with regard to the shell and OS. Patched by Steve Klabnik [Bug #8550]