Add the ability to change directories before execing.

base/process/launch.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file contains functions for launching subprocesses.
 
 #ifndef BASE_PROCESS_LAUNCH_H_
 #define BASE_PROCESS_LAUNCH_H_
 
 #include <string>
@@ skipping 126 matching lines @@
   // that is sent to the parent when the child dies. The termination signal will
   // always be set to SIGCHLD.
   int clone_flags;
 
   // By default, child processes will have the PR_SET_NO_NEW_PRIVS bit set. If
   // true, then this bit will not be set in the new child process.
   bool allow_new_privs;
 #endif  // defined(OS_LINUX)
 
 #if defined(OS_POSIX)
+  // If not empty, change to this directory before execing the new process.
+  base::FilePath current_directory;
+
   // If non-null, a delegate to be run immediately prior to executing the new
   // program in the child process.
   //
   // WARNING: If LaunchProcess is called in the presence of multiple threads,
   // code running in this delegate essentially needs to be async-signal safe
   // (see man 7 signal for a list of allowed functions).
   PreExecDelegate* pre_exec_delegate;
 #endif  // defined(OS_POSIX)
 
 #if defined(OS_CHROMEOS)
@@ skipping 149 matching lines @@
 // multiple threads are running, since at the time the fork happened, the
 // threads could have been in any state (potentially holding locks, etc.).
 // Callers should most likely call execve() in the child soon after calling
 // this.
 BASE_EXPORT pid_t ForkWithFlags(unsigned long flags, pid_t* ptid, pid_t* ctid);
 #endif
 
 }  // namespace base
 
 #endif  // BASE_PROCESS_LAUNCH_H_