batch file execution is forbidden by default

Addresses #522.

CMakeLists.txt

@@ -3,7 +3,7 @@
 # Distributed under the Boost Software License, Version 1.0.
 # https://www.boost.org/LICENSE_1_0.txt
 
-cmake_minimum_required(VERSION 3.5...3.16)
+cmake_minimum_required(VERSION 3.8...3.31)
 
 project(boost_process VERSION "${BOOST_SUPERPROJECT_VERSION}" LANGUAGES CXX)
 

README.md

@@ -6,8 +6,8 @@ Boost.process is a library for comfortable management of processes, released wit
 
 | Branches | Linux / Windows                                                                                                                              | Code coverage                                                                                                                                | Matrix                                                                                                                                        | 
 |----------|----------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------|
-| Develop: | [![Build Status](https://drone.cpp.al/api/badges/boostorg/process/status.svg)](https://drone.cpp.al/boostorg/process)                        | [![codecov](https://codecov.io/gh/boostorg/process/branch/develop/graph/badge.svg?token=AhunMqTSpA)](https://codecov.io/gh/boostorg/process) | [![Matrix](https://img.shields.io/badge/matrix-develop-lightgray.svg)](http://www.boost.org/development/tests/develop/developer/process.html) |
-| Master:  | [![Build Status](https://drone.cpp.al/api/badges/boostorg/process/status.svg?ref=refs/heads/develop)](https://drone.cpp.al/boostorg/process) | [![codecov](https://codecov.io/gh/boostorg/process/branch/master/graph/badge.svg?token=AhunMqTSpA)](https://codecov.io/gh/boostorg/process)  | [![Matrix](https://img.shields.io/badge/matrix-master-lightgray.svg)](http://www.boost.org/development/tests/master/developer/process.html)   |
+| Develop: | [![Build Status](https://drone.cpp.al/api/badges/boostorg/process/status.svg)](https://drone.cpp.al/boostorg/process)                        | [![codecov](https://codecov.io/gh/boostorg/process/branch/develop/graph/badge.svg?token=AhunMqTSpA)](https://codecov.io/gh/boostorg/process) | [![Matrix](https://img.shields.io/badge/matrix-develop-lightgray.svg)](https://regression.boost.io/develop/developer/process.html) |
+| Master:  | [![Build Status](https://drone.cpp.al/api/badges/boostorg/process/status.svg?ref=refs/heads/develop)](https://drone.cpp.al/boostorg/process) | [![codecov](https://codecov.io/gh/boostorg/process/branch/master/graph/badge.svg?token=AhunMqTSpA)](https://codecov.io/gh/boostorg/process)  | [![Matrix](https://img.shields.io/badge/matrix-master-lightgray.svg)](https://regression.boost.io/master/developer/process.html)   |
 
 
 

doc/reference/stdio.adoc

@@ -35,12 +35,57 @@ Valid initializers for any stdio are:
 
   - `std::nullptr_t` assigning a null-device
   - `FILE*` any open file, including `stdin`, `stdout` and `stderr`
-  - a filesystem::path, which will open a readable or writable depending on the direction of the stream
   - `native_handle` any native file handle (`HANDLE` on windows) or file descriptor (`int` on posix)
-  - any io-object with a .native_handle() function that is compatible with the above. E.g. a asio::ip::tcp::socket
-  - an asio::basic_writeable_pipe for stdin or asio::basic_readable_pipe for stderr/stdout.
+  - any io-object with a `.native_handle()` function that is compatible with the above. E.g. a `asio::ip::tcp::socket`, or a pipe object.
+  - a filesystem::path, which will open a readable or writable depending on the direction of the stream
+  - an `asio::basic_writeable_pipe` for stdin or `asio::basic_readable_pipe` for stderr/stdout.
 
+When passing a `FILE*`, a `native_handle` or an io-object with a `native_handle`,
+the initializer will assign the handle as is to the child process.
+That is the file descriptor/handle gets cloned into the subprocess and used without modification.
 
+When passing a filesystem::path, the initializer will attempt to open the file and then pass the handle 
+to the subprocess.
+
+When passing a `readable_pipe` to stdout/stderr or a `writable_pipe` to stdin by reference,
+the initializer to create the other side of the pipe (`writable_pipe` for stdout/stderr, `readable_pipe` for `stdin`),
+connect the pair and pass the native_handle to the child process.
+
+That is, these two are equivalent:
+
+.Implicit construction of the readable pipe.
+[source,cpp]
+----
+asio::io_context ctx;
+asio::writable_pipe wp{ctx};
+// create a readable pipe internally and connect it to wp
+process proc{ctx, "/bin/bash", {}, process_stdio{.in=wp}};
+
+// create it explicitly
+{
+  // the pipe the child process reads from
+  asio::readable_pipe rp{ctx}; 
+  asio::connect_pipe(rp, wp);
+  // `rp.native_handle()`  will be assigned to the child processes stdin
+  process proc{ctx, "/bin/bash", {}, process_stdio{.in=rp}};
+  rp.close(); // close it so the pipe closes when the `proc exits.
+}
+----
+
+The explicit version allows you to assign the same `writable_pipe` to `stdout` and `stderr`:
+
+[source,cpp]
+----
+// the pipe the parent process reads from and both 
+// stderr & stdout of the child process write to
+asio::readable_pipe rp{ctx};
+asio::writable_pipe wp{ctx}; 
+asio::connect_pipe(rp, wp);
+process proc{ctx, "/bin/bash", {}, process_stdio{.out=wp, .err=wp}};
+wp.close(); // close it so the pipe closes when the `proc exits.
+----
+
+NOTE: If the child writes to a pipe, the parent reads from it et vice versa.
 
 
 [source,cpp]
@@ -52,4 +97,4 @@ struct process_stdio
   __implementation_defined__ out;
   __implementation_defined__ err;
 };
-----
+----

include/boost/process/v1/detail/windows/basic_cmd.hpp

@@ -162,7 +162,9 @@ struct exe_cmd_init : handler_base_ext
     }
     static exe_cmd_init<Char> exe_args_shell(string_type && exe, std::vector<string_type> && args)
     {
-        std::vector<string_type> args_ = {c_arg(Char()), std::move(exe)};
+        std::vector<string_type> args_ = {c_arg(Char())};
+        if (!exe.empty())
+            args_.emplace_back(std::move(exe));
         args_.insert(args_.end(), std::make_move_iterator(args.begin()), std::make_move_iterator(args.end()));
         string_type sh = get_shell(Char());
 

include/boost/process/v2/detail/process_handle_fd.hpp

@@ -69,6 +69,8 @@ struct basic_process_handle_fd
     basic_process_handle_fd(executor_type executor, pid_type pid)
             : pid_(pid), descriptor_(executor, syscall(SYS_pidfd_open, pid, 0))
     {
+        if (descriptor_.native_handle() == -1)
+            detail::throw_error(detail::get_last_error(), "wait(pid)");
     }
 
     basic_process_handle_fd(executor_type executor, pid_type pid, native_handle_type process_handle)

include/boost/process/v2/detail/utf8.hpp

@@ -44,9 +44,14 @@ std::basic_string<CharOut, Traits, Allocator> conv_string(
     if (ec)
         detail::throw_error(ec, "size_as_utf8");
 
+
     std::basic_string<CharOut, Traits, Allocator> res(allocator);
     res.resize(req_size);
 
+    if (req_size == 0)
+        return res;
+
+
     auto res_size = convert_to_utf8(data, size, &res.front(), req_size,  ec);
     if (ec)
         detail::throw_error(ec, "convert_to_utf8");
@@ -70,6 +75,9 @@ std::basic_string<CharOut, Traits, Allocator> conv_string(
     std::basic_string<CharOut, Traits, Allocator> res(allocator);
     res.resize(req_size);
 
+    if (req_size == 0)
+        return res;
+
     auto res_size = convert_to_wide(data, size, &res.front(), req_size,  ec);
     if (ec)
         detail::throw_error(ec, "convert_to_wide");

include/boost/process/v2/environment.hpp

@@ -1762,9 +1762,12 @@ struct process_environment
   std::vector<environment::key_value_pair> env_buffer;
   std::vector<wchar_t> unicode_env;
 
-  BOOST_PROCESS_V2_DECL
   error_code on_setup(windows::default_launcher & launcher,
-                      const filesystem::path &, const std::wstring &);
+                      const filesystem::path &, const std::wstring &)
+  {
+    return do_setup(launcher);
+  }                  
+  BOOST_PROCESS_V2_DECL error_code do_setup(windows::default_launcher & launcher);
 
 #else
 
@@ -1813,7 +1816,13 @@ struct process_environment
 
   BOOST_PROCESS_V2_DECL
   error_code on_setup(posix::default_launcher & launcher, 
-                      const filesystem::path &, const char * const *);
+                      const filesystem::path &, const char * const *)
+  {
+    return do_setup(launcher);
+  }
+
+  BOOST_PROCESS_V2_DECL error_code do_setup(posix::default_launcher & launcher);
+
 
   std::vector<environment::key_value_pair> env_buffer;
   std::vector<const char *> env;

include/boost/process/v2/posix/default_launcher.hpp

@@ -352,9 +352,9 @@ struct default_launcher
             }
             fd_whitelist.push_back(pg.p[1]);
 
+#if !defined(BOOST_PROCESS_V2_DISABLE_NOTIFY_FORK)
             auto & ctx = net::query(
                     exec, net::execution::context);
-#if !defined(BOOST_PROCESS_V2_DISABLE_NOTIFY_FORK)
             ctx.notify_fork(net::execution_context::fork_prepare);
 #endif
             pid = ::fork();
@@ -386,7 +386,7 @@ struct default_launcher
                 ignore_unused(::write(pg.p[1], &errno, sizeof(int)));
                 BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
                 detail::on_exec_error(*this, executable, argv, ec, inits...);
-                ::exit(EXIT_FAILURE);
+                ::_exit(EXIT_FAILURE);
                 return basic_process<Executor>{exec};
             }
 #if !defined(BOOST_PROCESS_V2_DISABLE_NOTIFY_FORK)

include/boost/process/v2/posix/fork_and_forget_launcher.hpp

@@ -115,7 +115,7 @@ struct fork_and_forget_launcher : default_launcher
 
                 BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
                 detail::on_exec_error(*this, executable, argv, ec, inits...);
-                ::exit(EXIT_FAILURE);
+                ::_exit(EXIT_FAILURE);
                 return basic_process<Executor>{exec};
             }
 #if !defined(BOOST_PROCESS_V2_DISABLE_NOTIFY_FORK)

include/boost/process/v2/posix/pdfork_launcher.hpp

@@ -136,7 +136,7 @@ struct pdfork_launcher : default_launcher
                 default_launcher::ignore_unused(::write(pg.p[1], &errno, sizeof(int)));
                 BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
                 detail::on_exec_error(*this, executable, argv, ec, inits...);
-                ::exit(EXIT_FAILURE);
+                ::_exit(EXIT_FAILURE);
                 return basic_process<Executor>{exec};
             }
 #if !defined(BOOST_PROCESS_V2_DISABLE_NOTIFY_FORK)

include/boost/process/v2/posix/pipe_fork_launcher.hpp

@@ -140,7 +140,7 @@ struct pipe_fork_launcher : default_launcher
                 default_launcher::ignore_unused(::write(pg.p[1], &errno, sizeof(int)));
                 BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
                 detail::on_exec_error(*this, executable, argv, ec, inits...);
-                ::exit(EXIT_FAILURE);
+                ::_exit(EXIT_FAILURE);
                 return basic_process<Executor>{exec};
             }
             ctx.notify_fork(net::execution_context::fork_parent);

include/boost/process/v2/stdio.hpp

@@ -184,7 +184,7 @@ struct process_io_binding
   process_io_binding & operator=(const process_io_binding &) = delete;
 
   process_io_binding(process_io_binding && other) noexcept
-          : fd(other.fd), fd_needs_closing(other.fd), ec(other.ec)
+          : fd(other.fd), fd_needs_closing(other.fd_needs_closing), ec(other.ec)
   {
     other.fd = target;
     other.fd_needs_closing = false;

include/boost/process/v2/windows/default_launcher.hpp

@@ -225,6 +225,9 @@ struct default_launcher
                               INVALID_HANDLE_VALUE,
                               INVALID_HANDLE_VALUE},
                               nullptr};
+  /// Allow batch files to be executed, which might pose a security threat.
+  bool allow_batch_files = false;
+                              
   /// The process_information that gets assigned after a call to CreateProcess
   PROCESS_INFORMATION process_information{nullptr, nullptr, 0,0};
 
@@ -293,6 +296,12 @@ struct default_launcher
                   Args && args,
                   Inits && ... inits ) -> enable_init<Executor, Inits...>
   {
+    if (!allow_batch_files && ((executable.extension() == ".bat") || (executable.extension() == ".cmd")))
+    {
+       BOOST_PROCESS_V2_ASSIGN_EC(ec, ERROR_ACCESS_DENIED, system_category());
+       return basic_process<Executor>(exec);
+    }
+  
     auto command_line = this->build_command_line(executable, std::forward<Args>(args));
 
     ec = detail::on_setup(*this, executable, command_line, inits...);
@@ -352,7 +361,6 @@ struct default_launcher
   BOOST_PROCESS_V2_DECL static 
   std::size_t escape_argv_string(wchar_t * itr, std::size_t max_size, 
                                  basic_string_view<wchar_t> ws);
-                                        
 
 
 
@@ -395,6 +403,7 @@ struct default_launcher
                    {
                       return detail::conv_string<wchar_t>(arg.data(), arg.size());
                    });
+
     return build_command_line_impl(pt, argw, L"");
   }
 
@@ -406,10 +415,11 @@ struct default_launcher
     {
       std::wstring buffer;
       buffer.resize(escaped_argv_length(pt.native()));
-      escape_argv_string(&buffer.front(), buffer.size(), pt.native());
+      
+      if (!buffer.empty())
+        escape_argv_string(&buffer.front(), buffer.size(), pt.native());
       return buffer;
     }
-
     return build_command_line_impl(pt, args, *std::begin(args));
   }
 
@@ -438,4 +448,4 @@ BOOST_PROCESS_V2_END_NAMESPACE
 
 
 
-#endif //BOOST_PROCESS_V2_WINDOWS_DEFAULT_LAUNCHER_HPP
+#endif //BOOST_PROCESS_V2_WINDOWS_DEFAULT_LAUNCHER_HPP

src/environment.cpp

@@ -17,7 +17,7 @@ BOOST_PROCESS_V2_BEGIN_NAMESPACE
 
 #if defined(BOOST_PROCESS_V2_WINDOWS)
 
-error_code process_environment::on_setup(windows::default_launcher & launcher, const filesystem::path &, const std::wstring &)
+error_code process_environment::do_setup(windows::default_launcher & launcher)
 {
     if (!unicode_env.empty() && !ec)
     {
@@ -30,7 +30,7 @@ error_code process_environment::on_setup(windows::default_launcher & launcher, c
 
 #else
 
-error_code process_environment::on_setup(posix::default_launcher & launcher, const filesystem::path &, const char * const *)
+error_code process_environment::do_setup(posix::default_launcher & launcher)
 {
     launcher.env = env.data();
     return error_code{};

src/windows/default_launcher.cpp

@@ -24,54 +24,72 @@ namespace windows
     if (ws.empty())
       return 2u; // just quotes
 
-    constexpr static auto space = L' ';
     constexpr static auto quote = L'"';
+    const auto needs_quotes = ws.find_first_of(L" \t") != basic_string_view<wchar_t>::npos;
 
-    const auto has_space = ws.find(space) != basic_string_view<wchar_t>::npos;
-    const auto quoted = (ws.front() == quote) && (ws.back() == quote);
-    const auto needs_escape = has_space && !quoted ;
-
-    if (!needs_escape)
-      return ws.size();
-    else
-      return ws.size() + std::count(ws.begin(), ws.end(), quote) + 2u;
+    std::size_t needed_escapes = 0u;
+    for (auto itr = ws.begin(); itr != ws.end(); itr ++)
+    {
+      if (*itr == quote)
+        needed_escapes++;
+      else if (*itr == L'\\')
+      {
+        auto nx = std::next(itr);
+        if (nx != ws.end() && *nx == L'"')
+          needed_escapes ++;
+        else if (nx == ws.end())
+          needed_escapes ++;      
+      }
+    }
+    
+    return ws.size() + needed_escapes + (needs_quotes ? 2u : 0u);
   }
 
 
   std::size_t default_launcher::escape_argv_string(wchar_t * itr, std::size_t max_size, 
                                         basic_string_view<wchar_t> ws)
   { 
-    const auto sz = escaped_argv_length(ws);
+    constexpr static auto quote = L'"';
+    const auto needs_quotes = ws.find_first_of(L" \t") != basic_string_view<wchar_t>::npos;
+    const auto needed_escapes = std::count(ws.begin(), ws.end(), quote);
+    
+    const auto sz = ws.size() + needed_escapes + (needs_quotes ? 2u : 0u);
+    
     if (sz > max_size)
       return 0u;
+
     if (ws.empty())      
     {
-      itr[0] = L'"';
-      itr[1] = L'"';
+      itr[0] = quote;
+      itr[1] = quote;
       return 2u;
     }
 
-    const auto has_space = ws.find(L' ') != basic_string_view<wchar_t>::npos;
-    const auto quoted = (ws.front() == L'"') && (ws.back() ==  L'"');
-    const auto needs_escape = has_space && !quoted;
-
-    if (!needs_escape)
-      return std::copy(ws.begin(), ws.end(), itr) - itr;
-
-    if (sz < (2u + ws.size()))
-      return 0u;
-      
     const auto end = itr + sz; 
     const auto begin = itr;
-    *(itr ++) = L'"';
-    for (auto wc : ws)
+    if (needs_quotes)
+      *(itr++) = quote;
+
+    for (auto it = ws.begin(); it != ws.end(); it ++)
     {
-      if (wc == L'"')
+      if (*it == quote) // makes it \"
         *(itr++) = L'\\';
-      *(itr++) = wc;
+        
+      if (*it == L'\\') // \" needs to become \\\"
+      {
+        auto nx = std::next(it);
+        if (nx != ws.end() && *nx == L'"')
+          *(itr++) = L'\\';
+        else if (nx == ws.end())
+          *(itr++) = L'\\';
+
+      }
+
+      *(itr++) = *it;
     }
 
-    *(itr ++) = L'"';
+    if (needs_quotes)
+      *(itr++) = quote;
     return itr - begin;
   }
 
@@ -108,13 +126,18 @@ namespace windows
     auto tl = get_thread_attribute_list(ec);
     if (ec)
       return;
+    
+    auto itr  = std::unique(inherited_handles.begin(), inherited_handles.end());
+    auto size = std::distance(inherited_handles.begin(), itr);
+      
     if (!::UpdateProcThreadAttribute(
         tl, 0, PROC_THREAD_ATTRIBUTE_HANDLE_LIST,
-        inherited_handles.data(), inherited_handles.size() * sizeof(HANDLE), nullptr, nullptr))
+        inherited_handles.data(), size * sizeof(HANDLE), nullptr, nullptr))
       BOOST_PROCESS_V2_ASSIGN_LAST_ERROR(ec);
   }
 
 }
 BOOST_PROCESS_V2_END_NAMESPACE
 
-#endif
+#endif
+

test/v2/CMakeLists.txt

@@ -1,18 +1,12 @@
 enable_testing()
 
-add_library(boost_process_v2_test_impl test_impl.cpp)
-target_compile_definitions(boost_process_v2_test_impl PUBLIC -DBOOST_PROCESS_V2_SEPARATE_COMPILATION=1)
-
-if (WIN32)
-    target_compile_definitions(boost_process_v2_test_impl PUBLIC WIN32_LEAN_AND_MEAN=1)
-    target_link_libraries(boost_process_v2_test_impl Boost::process Boost::unit_test_framework Boost::process Ntdll)
-else()
-    target_link_libraries(boost_process_v2_test_impl Boost::process Boost::unit_test_framework Boost::process)
-endif()
-
 function(boost_process_v2_standalone_test name)
-    add_executable(boost_process_v2_${name} ${name}.cpp)
-    target_link_libraries(boost_process_v2_${name} Boost::process Boost::system Boost::filesystem boost_process_v2_test_impl)
+    add_executable(boost_process_v2_${name} ${name}.cpp test_impl.cpp)
+    target_link_libraries(boost_process_v2_${name} PUBLIC Boost::process Boost::system Boost::filesystem Boost::unit_test_framework )
+    if (WIN32)
+        target_compile_definitions(boost_process_v2_${name} PUBLIC WIN32_LEAN_AND_MEAN=1)
+        target_link_libraries(boost_process_v2_${name} PUBLIC Ntdll)
+    endif()
     add_test(NAME boost_process_v2_${name} COMMAND $<TARGET_FILE:boost_process_v2_${name}> )
 endfunction()
 
@@ -27,13 +21,16 @@ target_link_libraries(boost_process_v2_test_target PUBLIC Boost::process Boost::
 
 function(boost_process_v2_test_with_target name)
     add_executable(boost_process_v2_${name} ${name}.cpp)
-    target_link_libraries(boost_process_v2_${name} Boost::process Boost::system Boost::filesystem boost_process_v2_test_impl)
+    target_link_libraries(boost_process_v2_${name} PUBLIC Boost::process Boost::system Boost::filesystem boost_process_v2_test_impl)
+    if (WIN32)
+        target_compile_definitions(boost_process_v2_${name} PUBLIC WIN32_LEAN_AND_MEAN=1)
+        target_link_libraries(boost_process_v2_${name} PUBLIC Ntdll)
+    endif()    
     add_dependencies(boost_process_v2_${name} boost_process_v2_test_target)
     add_test(NAME boost_process_v2_${name} COMMAND $<TARGET_FILE:boost_process_v2_${name}>
                                                 -- $<TARGET_FILE:boost_process_v2_test_target>)
 
-
 endfunction()
 
 boost_process_v2_test_with_target(process)
-boost_process_v2_test_with_target(ext)
+boost_process_v2_test_with_target(ext)

test/v2/Jamfile.jam

@@ -33,7 +33,6 @@ project : requirements
   <os>NT,<toolset>cw:<library>ws2_32
   <os>NT,<toolset>gcc:<library>ws2_32
   <os>NT,<toolset>gcc:<library>Bcrypt
-  <define>BOOST_PROCESS_V2_SEPARATE_COMPILATION=1
   <library>/boost/test//included
 ;
 

test/v2/process.cpp

@@ -245,6 +245,83 @@ BOOST_AUTO_TEST_CASE(print_args_out)
 }
 
 
+BOOST_AUTO_TEST_CASE(print_args_spec_out)
+{
+    using boost::unit_test::framework::master_test_suite;
+    const auto pth =  master_test_suite().argv[1];
+
+    asio::io_context ctx;
+
+    asio::readable_pipe rp{ctx};
+    asio::writable_pipe wp{ctx};
+    asio::connect_pipe(rp, wp);
+
+    fprintf(stderr, "print_args_spec_out\n"); 
+    
+    bpv::process proc(ctx, pth, {"print-args", "&foo", "&", "", "\"\"", "\\\"", "|bar", "\"", "#foobar"}, 
+                                 bpv::process_stdio{/*in*/{},/*out*/wp, /*err*/ nullptr});
+    BOOST_CHECK(proc.running());                             
+
+    wp.close();
+    asio::streambuf st;
+    std::istream is{&st};
+    bpv::error_code ec;
+
+    auto sz = asio::read(rp, st,  ec);
+    while (ec == asio::error::interrupted)
+    sz += asio::read(rp, st,  ec);
+
+    BOOST_CHECK_NE(sz, 0u);
+    BOOST_CHECK_MESSAGE((ec == asio::error::broken_pipe) || (ec == asio::error::eof), ec.message());
+
+    std::string line;
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL(pth, line);
+
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL("print-args", line);
+
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL("&foo", line);
+
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL("&", line);
+
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL("", line);
+
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL("\"\"", line);
+
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL("\\\"", line);
+
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL("|bar", line);
+
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL("\"", line);
+
+
+    BOOST_CHECK(std::getline(is, line));
+    trim_end(line);
+    BOOST_CHECK_EQUAL("#foobar", line);
+
+
+    proc.wait();
+    BOOST_CHECK(proc.exit_code() == 0);
+}
+
+
 BOOST_AUTO_TEST_CASE(print_args_err)
 {
   using boost::unit_test::framework::master_test_suite;
@@ -791,5 +868,70 @@ BOOST_AUTO_TEST_CASE(async_terminate_code)
 #endif
 
 
+BOOST_AUTO_TEST_CASE(print_args_combined)
+{
+  using boost::unit_test::framework::master_test_suite;
+  const auto pth =  master_test_suite().argv[1];
+
+  asio::io_context ctx;
+
+  asio::readable_pipe rp{ctx};
+  asio::writable_pipe wp{ctx};
+  asio::connect_pipe(rp, wp);
+
+  bpv::process proc(ctx, pth, {"print-args", "bar", "foo"}, bpv::process_stdio{/*in*/{}, /*.out= */ wp, /* .err=*/ wp});
+  wp.close();
+
+  asio::streambuf st;
+  std::istream is{&st};
+  bpv::error_code ec;
+
+  auto sz = asio::read(rp, st,  ec);
+  while (ec == asio::error::interrupted)
+      sz += asio::read(rp, st,  ec);
+
+  BOOST_CHECK_NE(sz , 0u);
+  BOOST_CHECK_MESSAGE((ec == asio::error::broken_pipe) || (ec == asio::error::eof), ec.message());
+
+  std::string line;
+  BOOST_CHECK(std::getline(is, line));
+  trim_end(line);
+  BOOST_CHECK_EQUAL(pth, line );
+
+  BOOST_CHECK(std::getline(is, line));
+  trim_end(line);
+  BOOST_CHECK_EQUAL(pth, line );
+
+
+  BOOST_CHECK(std::getline(is, line));
+  trim_end(line);
+  BOOST_CHECK_EQUAL("print-args", line);
+
+  BOOST_CHECK(std::getline(is, line));
+  trim_end(line);
+  BOOST_CHECK_EQUAL("print-args", line);
+
+
+  BOOST_CHECK(std::getline(is, line));
+  trim_end(line);
+  BOOST_CHECK_EQUAL("bar", line);
+
+  BOOST_CHECK(std::getline(is, line));
+  trim_end(line);
+  BOOST_CHECK_EQUAL("bar", line);
+
+  BOOST_CHECK(std::getline(is, line));
+  trim_end(line);
+  BOOST_CHECK_EQUAL("foo", line);
+
+  BOOST_CHECK(std::getline(is, line));
+  trim_end(line);
+  BOOST_CHECK_EQUAL("foo", line);
+
+
+  proc.wait();
+  BOOST_CHECK_EQUAL(proc.exit_code(), 0);
+}
+
 BOOST_AUTO_TEST_SUITE_END();