Move testscript builtins to libbutl

1 files changed, 0 insertions, 1924 deletions

diff --git a/libbuild2/test/script/builtin.cxx b/libbuild2/test/script/builtin.cxx
deleted file mode 100644
index 06b0cec..0000000
--- a/libbuild2/test/script/builtin.cxx
+++ /dev/null
@@ -1,1924 +0,0 @@
-// file      : libbuild2/test/script/builtin.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <libbuild2/test/script/builtin.hxx>
-
-#include <chrono>
-#include <locale>
-#include <ostream>
-#include <sstream>
-#include <cstdlib> // strtoull()
-
-#include <libbutl/regex.mxx>
-#include <libbutl/path-io.mxx>    // use default operator<< implementation
-#include <libbutl/fdstream.mxx>   // fdopen_mode, fdstream_mode
-#include <libbutl/filesystem.mxx>
-
-#include <libbuild2/context.hxx> // sched
-
-#include <libbuild2/test/script/script.hxx>
-#include <libbuild2/test/script/builtin-options.hxx>
-
-// Strictly speaking a builtin which reads/writes from/to standard streams
-// must be asynchronous so that the caller can communicate with it through
-// pipes without being blocked on I/O operations. However, as an optimization,
-// we allow builtins that only print diagnostics to STDERR to be synchronous
-// assuming that their output will always fit the pipe buffer. Synchronous
-// builtins must not read from STDIN and write to STDOUT. Later we may relax
-// this rule to allow a "short" output for such builtins.
-//
-using namespace std;
-using namespace butl;
-
-namespace build2
-{
-  namespace test
-  {
-    namespace script
-    {
-      using builtin_impl = uint8_t (scope&,
-                                    const strings& args,
-                                    auto_fd in, auto_fd out, auto_fd err);
-
-      // Operation failed, diagnostics has already been issued.
-      //
-      struct failed {};
-
-      // Accumulate an error message, print it atomically in dtor to the
-      // provided stream and throw failed afterwards if requested. Prefixes
-      // the message with the builtin name.
-      //
-      // Move constructible-only, not assignable (based to diag_record).
-      //
-      class error_record
-      {
-      public:
-        template <typename T>
-        friend const error_record&
-        operator<< (const error_record& r, const T& x)
-        {
-          r.ss_ << x;
-          return r;
-        }
-
-        error_record (ostream& o, bool fail, const char* name)
-            : os_ (o), fail_ (fail), empty_ (false)
-        {
-          ss_ << name << ": ";
-        }
-
-        // Older versions of libstdc++ don't have the ostringstream move
-        // support. Luckily, GCC doesn't seem to be actually needing move due
-        // to copy/move elision.
-        //
-#ifdef __GLIBCXX__
-        error_record (error_record&&);
-#else
-        error_record (error_record&& r)
-            : os_ (r.os_),
-              ss_ (move (r.ss_)),
-              fail_ (r.fail_),
-              empty_ (r.empty_)
-        {
-          r.empty_ = true;
-        }
-#endif
-
-        ~error_record () noexcept (false)
-        {
-          if (!empty_)
-          {
-            // The output stream can be in a bad state (for example as a
-            // result of unsuccessful attempt to report a previous error), so
-            // we check it.
-            //
-            if (os_.good ())
-            {
-              ss_.put ('\n');
-              os_ << ss_.str ();
-              os_.flush ();
-            }
-
-            if (fail_)
-              throw failed ();
-          }
-        }
-
-      private:
-        ostream& os_;
-        mutable ostringstream ss_;
-
-        bool fail_;
-        bool empty_;
-      };
-
-      // Parse and normalize a path. Also, unless it is already absolute, make
-      // the path absolute using the specified directory. Throw invalid_path
-      // if the path is empty, and on parsing and normalization failures.
-      //
-      static path
-      parse_path (string s, const dir_path& d)
-      {
-        path p (move (s));
-
-        if (p.empty ())
-          throw invalid_path ("");
-
-        if (p.relative ())
-          p = d / move (p);
-
-        p.normalize ();
-        return p;
-      }
-
-      // Builtin commands functions.
-      //
-
-      // cat <file>...
-      //
-      // Note that POSIX doesn't specify if after I/O operation failure the
-      // command should proceed with the rest of the arguments. The current
-      // implementation exits immediatelly in such a case.
-      //
-      // @@ Shouldn't we check that we don't print a nonempty regular file to
-      //    itself, as that would merely exhaust the output device? POSIX
-      //    allows (but not requires) such a check and some implementations do
-      //    this. That would require to fstat() file descriptors and complicate
-      //    the code a bit. Was able to reproduce on a big file (should be
-      //    bigger than the stream buffer size) with the test
-      //    'cat file >+file'.
-      //
-      // Note: must be executed asynchronously.
-      //
-      static uint8_t
-      cat (scope& sp,
-           const strings& args,
-           auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "cat");
-        };
-
-        try
-        {
-          ifdstream cin  (move (in),  fdstream_mode::binary);
-          ofdstream cout (move (out), fdstream_mode::binary);
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          cat_options ops (scan); // Makes sure no options passed.
-
-          // Print files.
-          //
-          // Copy input stream to STDOUT.
-          //
-          auto copy = [&cout] (istream& is)
-          {
-            if (is.peek () != ifdstream::traits_type::eof ())
-              cout << is.rdbuf ();
-
-            is.clear (istream::eofbit); // Sets eofbit.
-          };
-
-          // Path of a file being printed to STDOUT. An empty path represents
-          // STDIN. Used in diagnostics.
-          //
-          path p;
-
-          try
-          {
-            // Print STDIN.
-            //
-            if (!scan.more ())
-              copy (cin);
-
-            // Print files.
-            //
-            while (scan.more ())
-            {
-              string f (scan.next ());
-
-              if (f == "-")
-              {
-                if (!cin.eof ())
-                {
-                  p.clear ();
-                  copy (cin);
-                }
-
-                continue;
-              }
-
-              p = parse_path (move (f), sp.wd_path);
-
-              ifdstream is (p, fdopen_mode::binary);
-              copy (is);
-              is.close ();
-            }
-          }
-          catch (const io_error& e)
-          {
-            error_record d (error ());
-            d << "unable to print ";
-
-            if (p.empty ())
-              d << "stdin";
-            else
-              d << "'" << p << "'";
-
-            d << ": " << e;
-          }
-
-          cin.close ();
-          cout.close ();
-          r = 0;
-        }
-        catch (const invalid_path& e)
-        {
-          error (false) << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while creating/closing cin, cout or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // Make a copy of a file at the specified path, preserving permissions,
-      // and registering a cleanup for a newly created file. The file paths
-      // must be absolute. Fail if an exception is thrown by the underlying
-      // copy operation.
-      //
-      static void
-      cpfile (scope& sp,
-              const path& from, const path& to,
-              bool overwrite,
-              bool attrs,
-              bool cleanup,
-              const function<error_record()>& fail)
-      {
-        try
-        {
-          bool exists (file_exists (to));
-
-          cpflags f (
-            overwrite
-            ? cpflags::overwrite_permissions | cpflags::overwrite_content
-            : cpflags::none);
-
-          if (attrs)
-            f |= cpflags::overwrite_permissions | cpflags::copy_timestamps;
-
-          cpfile (from, to, f);
-
-          if (!exists && cleanup)
-            sp.clean ({cleanup_type::always, to}, true /* implicit */);
-        }
-        catch (const system_error& e)
-        {
-          fail () << "unable to copy file '" << from << "' to '" << to
-                  << "': " << e;
-        }
-      }
-
-      // Make a copy of a directory at the specified path, registering a
-      // cleanup for the created directory. The directory paths must be
-      // absolute. Fail if the destination directory already exists or
-      // an exception is thrown by the underlying copy operation.
-      //
-      static void
-      cpdir (scope& sp,
-             const dir_path& from, const dir_path& to,
-             bool attrs,
-             bool cleanup,
-             const function<error_record()>& fail)
-      {
-        try
-        {
-          if (try_mkdir (to) == mkdir_status::already_exists)
-            throw_generic_error (EEXIST);
-
-          if (cleanup)
-            sp.clean ({cleanup_type::always, to}, true /* implicit */);
-
-          for (const auto& de: dir_iterator (from,
-                                             false /* ignore_dangling */))
-          {
-            path f (from / de.path ());
-            path t (to / de.path ());
-
-            if (de.type () == entry_type::directory)
-              cpdir (sp,
-                     path_cast<dir_path> (move (f)),
-                     path_cast<dir_path> (move (t)),
-                     attrs,
-                     cleanup,
-                     fail);
-            else
-              cpfile (sp, f, t, false /* overwrite */, attrs, cleanup, fail);
-          }
-
-          // Note that it is essential to copy timestamps and permissions after
-          // the directory content is copied.
-          //
-          if (attrs)
-          {
-            path_permissions (to, path_permissions (from));
-            dir_time (to, dir_time (from));
-          }
-        }
-        catch (const system_error& e)
-        {
-          fail () << "unable to copy directory '" << from << "' to '" << to
-                  << "': " << e;
-        }
-      }
-
-      // cp [-p|--preserve] [--no-cleanup]                   <src-file>    <dst-file>
-      // cp [-p|--preserve] [--no-cleanup] -R|-r|--recursive <src-dir>     <dst-dir>
-      // cp [-p|--preserve] [--no-cleanup]                   <src-file>... <dst-dir>/
-      // cp [-p|--preserve] [--no-cleanup] -R|-r|--recursive <src-path>... <dst-dir>/
-      //
-      // Note: can be executed synchronously.
-      //
-      static uint8_t
-      cp (scope& sp,
-          const strings& args,
-          auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "cp");
-        };
-
-        try
-        {
-          in.close ();
-          out.close ();
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          cp_options ops (scan);
-
-          // Copy files or directories.
-          //
-          if (!scan.more ())
-            error () << "missing arguments";
-
-          // Note that the arguments semantics depends on the last argument,
-          // so we read out and cache them.
-          //
-          small_vector<string, 2> args;
-          while (scan.more ())
-            args.push_back (scan.next ());
-
-          const dir_path& wd (sp.wd_path);
-
-          auto i (args.begin ());
-          auto j (args.rbegin ());
-          path dst (parse_path (move (*j++), wd));
-          auto e (j.base ());
-
-          if (i == e)
-            error () << "missing source path";
-
-          auto fail = [&error] () {return error (true);};
-
-          bool cleanup (!ops.no_cleanup ());
-
-          // If destination is not a directory path (no trailing separator)
-          // then make a copy of the filesystem entry at the specified path
-          // (the only source path is allowed in such a case). Otherwise copy
-          // the source filesystem entries into the destination directory.
-          //
-          if (!dst.to_directory ())
-          {
-            path src (parse_path (move (*i++), wd));
-
-            // If there are multiple sources but no trailing separator for the
-            // destination, then, most likelly, it is missing.
-            //
-            if (i != e)
-              error () << "multiple source paths without trailing separator "
-                       << "for destination directory";
-
-            if (!ops.recursive ())
-              // Synopsis 1: make a file copy at the specified path.
-              //
-              cpfile (sp,
-                      src,
-                      dst,
-                      true /* overwrite */,
-                      ops.preserve (),
-                      cleanup,
-                      fail);
-            else
-              // Synopsis 2: make a directory copy at the specified path.
-              //
-              cpdir (sp,
-                     path_cast<dir_path> (src), path_cast<dir_path> (dst),
-                     ops.preserve (),
-                     cleanup,
-                     fail);
-          }
-          else
-          {
-            for (; i != e; ++i)
-            {
-              path src (parse_path (move (*i), wd));
-
-              if (ops.recursive () && dir_exists (src))
-                // Synopsis 4: copy a filesystem entry into the specified
-                // directory. Note that we handle only source directories here.
-                // Source files are handled below.
-                //
-                cpdir (sp,
-                       path_cast<dir_path> (src),
-                       path_cast<dir_path> (dst / src.leaf ()),
-                       ops.preserve (),
-                       cleanup,
-                       fail);
-              else
-                // Synopsis 3: copy a file into the specified directory. Also,
-                // here we cover synopsis 4 for the source path being a file.
-                //
-                cpfile (sp,
-                        src,
-                        dst / src.leaf (),
-                        true /* overwrite */,
-                        ops.preserve (),
-                        cleanup,
-                        fail);
-            }
-          }
-
-          r = 0;
-        }
-        catch (const invalid_path& e)
-        {
-          error (false) << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while closing in, out or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // echo <string>...
-      //
-      // Note: must be executed asynchronously.
-      //
-      static uint8_t
-      echo (scope&,
-            const strings& args,
-            auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        try
-        {
-          in.close ();
-          ofdstream cout (move (out));
-
-          for (auto b (args.begin ()), i (b), e (args.end ()); i != e; ++i)
-            cout << (i != b ? " " : "") << *i;
-
-          cout << '\n';
-          cout.close ();
-          r = 0;
-        }
-        catch (const std::exception& e)
-        {
-          cerr << "echo: " << e << endl;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // false
-      //
-      // Failure to close the file descriptors is silently ignored.
-      //
-      // Note: can be executed synchronously.
-      //
-      static builtin
-      false_ (scope&, uint8_t& r, const strings&, auto_fd, auto_fd, auto_fd)
-      {
-        return builtin (r = 1);
-      }
-
-      // true
-      //
-      // Failure to close the file descriptors is silently ignored.
-      //
-      // Note: can be executed synchronously.
-      //
-      static builtin
-      true_ (scope&, uint8_t& r, const strings&, auto_fd, auto_fd, auto_fd)
-      {
-        return builtin (r = 0);
-      }
-
-      // Create a symlink to a file or directory at the specified path. The
-      // paths must be absolute. Fall back to creating a hardlink, if symlink
-      // creation is not supported for the link path. If hardlink creation is
-      // not supported either, then fall back to copies. If requested, created
-      // filesystem entries are registered for cleanup. Fail if the target
-      // filesystem entry doesn't exist or an exception is thrown by the
-      // underlying filesystem operation (specifically for an already existing
-      // filesystem entry at the link path).
-      //
-      // Note that supporting optional removal of an existing filesystem entry
-      // at the link path (the -f option) tends to get hairy. As soon as an
-      // existing and the resulting filesystem entries could be of different
-      // types, we would end up with canceling an old cleanup and registering
-      // the new one. Also removing non-empty directories doesn't look very
-      // natural, but would be required if we want the behavior on POSIX and
-      // Windows to be consistent.
-      //
-      static void
-      mksymlink (scope& sp,
-                 const path& target, const path& link,
-                 bool cleanup,
-                 const function<error_record()>& fail)
-      {
-        // Determine the target type, fail if the target doesn't exist.
-        //
-        bool dir (false);
-
-        try
-        {
-          pair<bool, entry_stat> pe (path_entry (target));
-
-          if (!pe.first)
-            fail () << "unable to create symlink to '" << target << "': "
-                    << "no such file or directory";
-
-          dir = pe.second.type == entry_type::directory;
-        }
-        catch (const system_error& e)
-        {
-          fail () << "unable to stat '" << target << "': " << e;
-        }
-
-        // First we try to create a symlink. If that fails (e.g., "Windows
-        // happens"), then we resort to hard links. If that doesn't work out
-        // either (e.g., not on the same filesystem), then we fall back to
-        // copies. So things are going to get a bit nested.
-        //
-        // Note: similar to mkanylink() but with support for directories.
-        //
-        try
-        {
-          mksymlink (target, link, dir);
-
-          if (cleanup)
-            sp.clean ({cleanup_type::always, link}, true /* implicit */);
-        }
-        catch (const system_error& e)
-        {
-          // Note that we are not guaranteed (here and below) that the
-          // system_error exception is of the generic category.
-          //
-          int c (e.code ().value ());
-          if (!(e.code ().category () == generic_category () &&
-                (c == ENOSYS || // Not implemented.
-                 c == EPERM)))  // Not supported by the filesystem(s).
-            fail () << "unable to create symlink '" << link << "' to '"
-                    << target << "': " << e;
-
-          try
-          {
-            mkhardlink (target, link, dir);
-
-            if (cleanup)
-              sp.clean ({cleanup_type::always, link}, true /* implicit */);
-          }
-          catch (const system_error& e)
-          {
-            c = e.code ().value ();
-            if (!(e.code ().category () == generic_category () &&
-                  (c == ENOSYS || // Not implemented.
-                   c == EPERM  || // Not supported by the filesystem(s).
-                   c == EXDEV)))  // On different filesystems.
-              fail () << "unable to create hardlink '" << link << "' to '"
-                      << target << "': " << e;
-
-            if (dir)
-              cpdir (sp,
-                     path_cast<dir_path> (target), path_cast<dir_path> (link),
-                     false,
-                     cleanup,
-                     fail);
-            else
-              cpfile (sp,
-                      target,
-                      link,
-                      false /* overwrite */,
-                      true /* attrs */,
-                      cleanup,
-                      fail);
-          }
-        }
-      }
-
-      // ln [--no-cleanup] -s|--symbolic <target-path>    <link-path>
-      // ln [--no-cleanup] -s|--symbolic <target-path>... <link-dir>/
-      //
-      // Note: can be executed synchronously.
-      //
-      static uint8_t
-      ln (scope& sp,
-          const strings& args,
-          auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "ln");
-        };
-
-        try
-        {
-          in.close ();
-          out.close ();
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          ln_options ops (scan);
-
-          if (!ops.symbolic ())
-            error () << "missing -s|--symbolic option";
-
-          // Create file or directory symlinks.
-          //
-          if (!scan.more ())
-            error () << "missing arguments";
-
-          // Note that the arguments semantics depends on the last argument,
-          // so we read out and cache them.
-          //
-          small_vector<string, 2> args;
-          while (scan.more ())
-            args.push_back (scan.next ());
-
-          const dir_path& wd (sp.wd_path);
-
-          auto i (args.begin ());
-          auto j (args.rbegin ());
-          path link (parse_path (move (*j++), wd));
-          auto e (j.base ());
-
-          if (i == e)
-            error () << "missing target path";
-
-          auto fail = [&error] () {return error (true);};
-
-          bool cleanup (!ops.no_cleanup ());
-
-          // If link is not a directory path (no trailing separator), then
-          // create a symlink to the target path at the specified link path
-          // (the only target path is allowed in such a case). Otherwise create
-          // links to the target paths inside the specified directory.
-          //
-          if (!link.to_directory ())
-          {
-            path target (parse_path (move (*i++), wd));
-
-            // If there are multiple targets but no trailing separator for the
-            // link, then, most likelly, it is missing.
-            //
-            if (i != e)
-              error () << "multiple target paths with non-directory link path";
-
-            // Synopsis 1: create a target path symlink at the specified path.
-            //
-            mksymlink (sp, target, link, cleanup, fail);
-          }
-          else
-          {
-            for (; i != e; ++i)
-            {
-              path target (parse_path (move (*i), wd));
-
-              // Synopsis 2: create a target path symlink in the specified
-              // directory.
-              //
-              mksymlink (sp, target, link / target.leaf (), cleanup, fail);
-            }
-          }
-
-          r = 0;
-        }
-        catch (const invalid_path& e)
-        {
-          error (false) << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while closing in, out or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // Create a directory if not exist and its parent directories if
-      // necessary. Throw system_error on failure. Register created
-      // directories for cleanup. The directory path must be absolute.
-      //
-      static void
-      mkdir_p (scope& sp, const dir_path& p, bool cleanup)
-      {
-        if (!dir_exists (p))
-        {
-          if (!p.root ())
-            mkdir_p (sp, p.directory (), cleanup);
-
-          try_mkdir (p); // Returns success or throws.
-
-          if (cleanup)
-            sp.clean ({cleanup_type::always, p}, true /* implicit */);
-        }
-      }
-
-      // mkdir [--no-cleanup] [-p|--parents] <dir>...
-      //
-      // Note that POSIX doesn't specify if after a directory creation failure
-      // the command should proceed with the rest of the arguments. The current
-      // implementation exits immediatelly in such a case.
-      //
-      // Note: can be executed synchronously.
-      //
-      static uint8_t
-      mkdir (scope& sp,
-             const strings& args,
-             auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "mkdir");
-        };
-
-        try
-        {
-          in.close ();
-          out.close ();
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          mkdir_options ops (scan);
-
-          // Create directories.
-          //
-          if (!scan.more ())
-            error () << "missing directory";
-
-          bool cleanup (!ops.no_cleanup ());
-
-          while (scan.more ())
-          {
-            dir_path p (path_cast<dir_path> (parse_path (scan.next (),
-                                                         sp.wd_path)));
-
-            try
-            {
-              if (ops.parents ())
-                mkdir_p (sp, p, cleanup);
-              else if (try_mkdir (p) == mkdir_status::success)
-              {
-                if (cleanup)
-                  sp.clean ({cleanup_type::always, p}, true /* implicit */);
-              }
-              else //                == mkdir_status::already_exists
-                throw_generic_error (EEXIST);
-            }
-            catch (const system_error& e)
-            {
-              error () << "unable to create directory '" << p << "': " << e;
-            }
-          }
-
-          r = 0;
-        }
-        catch (const invalid_path& e)
-        {
-          error (false) << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while closing in, out or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // mv [--no-cleanup] [-f|--force] <src-path>    <dst-path>
-      // mv [--no-cleanup] [-f|--force] <src-path>... <dst-dir>/
-      //
-      // Note: can be executed synchronously.
-      //
-      static uint8_t
-      mv (scope& sp,
-          const strings& args,
-          auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "mv");
-        };
-
-        try
-        {
-          in.close ();
-          out.close ();
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          mv_options ops (scan);
-
-          // Move filesystem entries.
-          //
-          if (!scan.more ())
-            error () << "missing arguments";
-
-          // Note that the arguments semantics depends on the last argument,
-          // so we read out and cache them.
-          //
-          small_vector<string, 2> args;
-          while (scan.more ())
-            args.push_back (scan.next ());
-
-          const dir_path& wd (sp.wd_path);
-
-          auto i (args.begin ());
-          auto j (args.rbegin ());
-          path dst (parse_path (move (*j++), wd));
-          auto e (j.base ());
-
-          if (i == e)
-            error () << "missing source path";
-
-          auto mv = [ops, &wd, &sp, &error] (const path& from, const path& to)
-          {
-            const dir_path& rwd (sp.root.wd_path);
-
-            if (!from.sub (rwd) && !ops.force ())
-              error () << "'" << from << "' is out of working directory '"
-                       << rwd << "'";
-
-            try
-            {
-              auto check_wd = [&wd, &error] (const path& p)
-              {
-                if (wd.sub (path_cast<dir_path> (p)))
-                  error () << "'" << p << "' contains test working directory '"
-                           << wd << "'";
-              };
-
-              check_wd (from);
-              check_wd (to);
-
-              bool exists (butl::entry_exists (to));
-
-              // Fail if the source and destination paths are the same.
-              //
-              // Note that for mventry() function (that is based on the POSIX
-              // rename() function) this is a noop.
-              //
-              if (exists && to == from)
-                error () << "unable to move entity '" << from << "' to itself";
-
-              // Rename/move the filesystem entry, replacing an existing one.
-              //
-              mventry (from,
-                       to,
-                       cpflags::overwrite_permissions |
-                       cpflags::overwrite_content);
-
-              // Unless suppressed, adjust the cleanups that are sub-paths of
-              // the source path.
-              //
-              if (!ops.no_cleanup ())
-              {
-                // "Move" the matching cleanup if the destination path doesn't
-                // exist and is a sub-path of the working directory. Otherwise
-                // just remove it.
-                //
-                // Note that it's not enough to just change the cleanup paths.
-                // We also need to make sure that these cleanups happen before
-                // the destination directory (or any of its parents) cleanup,
-                // that is potentially registered. To achieve that we can just
-                // relocate these cleanup entries to the end of the list,
-                // preserving their mutual order. Remember that cleanups in
-                // the list are executed in the reversed order.
-                //
-                bool mv_cleanups (!exists && to.sub (rwd));
-                cleanups cs;
-
-                // Remove the source path sub-path cleanups from the list,
-                // adjusting/caching them if required (see above).
-                //
-                for (auto i (sp.cleanups.begin ()); i != sp.cleanups.end (); )
-                {
-                  cleanup& c (*i);
-                  path&    p (c.path);
-
-                  if (p.sub (from))
-                  {
-                    if (mv_cleanups)
-                    {
-                      // Note that we need to preserve the cleanup path
-                      // trailing separator which indicates the removal
-                      // method. Also note that leaf(), in particular, does
-                      // that.
-                      //
-                      p = p != from
-                        ? to / p.leaf (path_cast<dir_path> (from))
-                        : p.to_directory ()
-                          ? path_cast<dir_path> (to)
-                          : to;
-
-                      cs.push_back (move (c));
-                    }
-
-                    i = sp.cleanups.erase (i);
-                  }
-                  else
-                    ++i;
-                }
-
-                // Re-insert the adjusted cleanups at the end of the list.
-                //
-                sp.cleanups.insert (sp.cleanups.end (),
-                                    make_move_iterator (cs.begin ()),
-                                    make_move_iterator (cs.end ()));
-              }
-            }
-            catch (const system_error& e)
-            {
-              error () << "unable to move entity '" << from << "' to '" << to
-                       << "': " << e;
-            }
-          };
-
-          // If destination is not a directory path (no trailing separator)
-          // then move the filesystem entry to the specified path (the only
-          // source path is allowed in such a case). Otherwise move the source
-          // filesystem entries into the destination directory.
-          //
-          if (!dst.to_directory ())
-          {
-            path src (parse_path (move (*i++), wd));
-
-            // If there are multiple sources but no trailing separator for the
-            // destination, then, most likelly, it is missing.
-            //
-            if (i != e)
-              error () << "multiple source paths without trailing separator "
-                       << "for destination directory";
-
-            // Synopsis 1: move an entity to the specified path.
-            //
-            mv (src, dst);
-          }
-          else
-          {
-            // Synopsis 2: move entities into the specified directory.
-            //
-            for (; i != e; ++i)
-            {
-              path src (parse_path (move (*i), wd));
-              mv (src, dst / src.leaf ());
-            }
-          }
-
-          r = 0;
-        }
-        catch (const invalid_path& e)
-        {
-          error (false) << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while closing in, out or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // rm [-r|--recursive] [-f|--force] <path>...
-      //
-      // The implementation deviates from POSIX in a number of ways. It doesn't
-      // interact with a user and fails immediatelly if unable to process an
-      // argument. It doesn't check for dots containment in the path, and
-      // doesn't consider files and directory permissions in any way just
-      // trying to remove a filesystem entry. Always fails if empty path is
-      // specified.
-      //
-      // Note: can be executed synchronously.
-      //
-      static uint8_t
-      rm (scope& sp,
-          const strings& args,
-          auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "rm");
-        };
-
-        try
-        {
-          in.close ();
-          out.close ();
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          rm_options ops (scan);
-
-          // Remove entries.
-          //
-          if (!scan.more () && !ops.force ())
-            error () << "missing file";
-
-          const dir_path& wd  (sp.wd_path);
-          const dir_path& rwd (sp.root.wd_path);
-
-          while (scan.more ())
-          {
-            path p (parse_path (scan.next (), wd));
-
-            if (!p.sub (rwd) && !ops.force ())
-              error () << "'" << p << "' is out of working directory '" << rwd
-                       << "'";
-
-            try
-            {
-              dir_path d (path_cast<dir_path> (p));
-
-              if (dir_exists (d))
-              {
-                if (!ops.recursive ())
-                  error () << "'" << p << "' is a directory";
-
-                if (wd.sub (d))
-                  error () << "'" << p << "' contains test working directory '"
-                           << wd << "'";
-
-                // The call can result in rmdir_status::not_exist. That's not
-                // very likelly but there is also nothing bad about it.
-                //
-                try_rmdir_r (d);
-              }
-              else if (try_rmfile (p) == rmfile_status::not_exist &&
-                       !ops.force ())
-                throw_generic_error (ENOENT);
-            }
-            catch (const system_error& e)
-            {
-              error () << "unable to remove '" << p << "': " << e;
-            }
-          }
-
-          r = 0;
-        }
-        catch (const invalid_path& e)
-        {
-          error (false) << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while closing in, out or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // rmdir [-f|--force] <path>...
-      //
-      // Note: can be executed synchronously.
-      //
-      static uint8_t
-      rmdir (scope& sp,
-             const strings& args,
-             auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "rmdir");
-        };
-
-        try
-        {
-          in.close ();
-          out.close ();
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          rmdir_options ops (scan);
-
-          // Remove directories.
-          //
-          if (!scan.more () && !ops.force ())
-            error () << "missing directory";
-
-          const dir_path& wd  (sp.wd_path);
-          const dir_path& rwd (sp.root.wd_path);
-
-          while (scan.more ())
-          {
-            dir_path p (path_cast<dir_path> (parse_path (scan.next (), wd)));
-
-            if (wd.sub (p))
-              error () << "'" << p << "' contains test working directory '"
-                       << wd << "'";
-
-            if (!p.sub (rwd) && !ops.force ())
-              error () << "'" << p << "' is out of working directory '"
-                       << rwd << "'";
-
-            try
-            {
-              rmdir_status s (try_rmdir (p));
-
-              if (s == rmdir_status::not_empty)
-                throw_generic_error (ENOTEMPTY);
-              else if (s == rmdir_status::not_exist && !ops.force ())
-                throw_generic_error (ENOENT);
-            }
-            catch (const system_error& e)
-            {
-              error () << "unable to remove '" << p << "': " << e;
-            }
-          }
-
-          r = 0;
-        }
-        catch (const invalid_path& e)
-        {
-          error (false) << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while closing in, out or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // sed [-n|--quiet] [-i|--in-place] -e|--expression <script> [<file>]
-      //
-      // Note: must be executed asynchronously.
-      //
-      static uint8_t
-      sed (scope& sp,
-           const strings& args,
-           auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "sed");
-        };
-
-        try
-        {
-          // Automatically remove a temporary file (used for in place editing)
-          // on failure.
-          //
-          auto_rmfile rm;
-
-          // Do not throw when failbit is set (getline() failed to extract any
-          // character).
-          //
-          ifdstream cin  (move (in), ifdstream::badbit);
-          ofdstream cout (move (out));
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          sed_options ops (scan);
-
-          if (ops.expression ().empty ())
-            error () << "missing script";
-
-          // Only a single script is supported.
-          //
-          if (ops.expression ().size () != 1)
-            error () << "multiple scripts";
-
-          struct
-          {
-            string regex;
-            string replacement;
-            bool icase  = false;
-            bool global = false;
-            bool print  = false;
-          } subst;
-
-          {
-            const string& v (ops.expression ()[0]);
-            if (v.empty ())
-              error () << "empty script";
-
-            if (v[0] != 's')
-              error () << "only 's' command supported";
-
-            // Parse the substitute command.
-            //
-            if (v.size () < 2)
-              error () << "no delimiter for 's' command";
-
-            char delim (v[1]);
-            if (delim == '\\' || delim == '\n')
-              error () << "invalid delimiter for 's' command";
-
-            size_t p (v.find (delim, 2));
-            if (p == string::npos)
-              error () << "unterminated 's' command regex";
-
-            subst.regex.assign (v, 2, p - 2);
-
-            // Empty regex matches nothing, so not of much use.
-            //
-            if (subst.regex.empty ())
-              error () << "empty regex in 's' command";
-
-            size_t b (p + 1);
-            p = v.find (delim, b);
-            if (p == string::npos)
-              error () << "unterminated 's' command replacement";
-
-            subst.replacement.assign (v, b, p - b);
-
-            // Parse the substitute command flags.
-            //
-            char c;
-            for (++p; (c = v[p]) != '\0'; ++p)
-            {
-              switch (c)
-              {
-              case 'i': subst.icase  = true; break;
-              case 'g': subst.global = true; break;
-              case 'p': subst.print  = true; break;
-              default:
-                {
-                  error () << "invalid 's' command flag '" << c << "'";
-                }
-              }
-            }
-          }
-
-          // Path of a file to edit. An empty path represents stdin.
-          //
-          path p;
-          if (scan.more ())
-          {
-            string f (scan.next ());
-
-            if (f != "-")
-              p = parse_path (move (f), sp.wd_path);
-          }
-
-          if (scan.more ())
-            error () << "unexpected argument '" << scan.next () << "'";
-
-          // Edit file.
-          //
-          // If we edit file in place make sure that the file path is specified
-          // and obtain a temporary file path. We will be writing to the
-          // temporary file (rather than to stdout) and will move it to the
-          // original file path afterwards.
-          //
-          path tp;
-          if (ops.in_place ())
-          {
-            if (p.empty ())
-              error () << "-i|--in-place option specified while reading from "
-                       << "stdin";
-
-            try
-            {
-              tp = path::temp_path ("build2-sed");
-
-              cout.close ();  // Flush and close.
-
-              cout.open (
-                fdopen (tp,
-                        fdopen_mode::out | fdopen_mode::truncate |
-                        fdopen_mode::create,
-                        path_permissions (p)));
-            }
-            catch (const io_error& e)
-            {
-              error_record d (error ());
-              d << "unable to open '" << tp << "': " << e;
-            }
-            catch (const system_error& e)
-            {
-              error_record d (error ());
-              d << "unable to obtain temporary file: " << e;
-            }
-
-            rm = auto_rmfile (tp);
-          }
-
-          // Note that ECMAScript is implied if no grammar flag is specified.
-          //
-          regex re (subst.regex,
-                    subst.icase ? regex::icase : regex::ECMAScript);
-
-          // Edit a file or STDIN.
-          //
-          try
-          {
-            // Open a file if specified.
-            //
-            if (!p.empty ())
-            {
-              cin.close (); // Flush and close.
-              cin.open (p);
-            }
-
-            // Read until failbit is set (throw on badbit).
-            //
-            string s;
-            while (getline (cin, s))
-            {
-              auto r (regex_replace_search (
-                        s,
-                        re,
-                        subst.replacement,
-                        subst.global
-                        ? regex_constants::format_default
-                        : regex_constants::format_first_only));
-
-              // Add newline regardless whether the source line is newline-
-              // terminated or not (in accordance with POSIX).
-              //
-              if (!ops.quiet () || (r.second && subst.print))
-                cout << r.first << '\n';
-            }
-
-            cin.close ();
-            cout.close ();
-
-            if (ops.in_place ())
-            {
-              mvfile (
-                tp, p,
-                cpflags::overwrite_content | cpflags::overwrite_permissions);
-
-              rm.cancel ();
-            }
-
-            r = 0;
-          }
-          catch (const io_error& e)
-          {
-            error_record d (error ());
-            d << "unable to edit ";
-
-            if (p.empty ())
-              d << "stdin";
-            else
-              d << "'" << p << "'";
-
-            d << ": " << e;
-          }
-        }
-        catch (const regex_error& e)
-        {
-          // Print regex_error description if meaningful (no space).
-          //
-          error (false) << "invalid regex" << e;
-        }
-        catch (const invalid_path& e)
-        {
-          error (false) << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while creating cin, cout or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const system_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // sleep <seconds>
-      //
-      // Note: can be executed synchronously.
-      //
-      static uint8_t
-      sleep (scope& s,
-             const strings& args,
-             auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "sleep");
-        };
-
-        try
-        {
-          in.close ();
-          out.close ();
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          sleep_options ops (scan); // Makes sure no options passed.
-
-          if (!scan.more ())
-            error () << "missing time interval";
-
-          uint64_t n;
-
-          for (;;) // Breakout loop.
-          {
-            string a (scan.next ());
-
-            // Note: strtoull() allows these.
-            //
-            if (!a.empty () && a[0] != '-' && a[0] != '+')
-            {
-              char* e (nullptr);
-              n = strtoull (a.c_str (), &e, 10); // Can't throw.
-
-              if (errno != ERANGE && e == a.c_str () + a.size ())
-                break;
-            }
-
-            error () << "invalid time interval '" << a << "'";
-          }
-
-          if (scan.more ())
-            error () << "unexpected argument '" << scan.next () << "'";
-
-          // Sleep.
-          //
-          // If/when required we could probably support the precise sleep mode
-          // (e.g., via an option).
-          //
-          s.root.test_target.ctx.sched.sleep (chrono::seconds (n));
-
-          r = 0;
-        }
-        // Can be thrown while closing in, out or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // test (-f|--file)|(-d|--directory) <path>
-      //
-      // Note: can be executed synchronously.
-      //
-      static uint8_t
-      test (scope& sp,
-            const strings& args,
-            auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (2);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "test");
-        };
-
-        try
-        {
-          in.close ();
-          out.close ();
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          test_options ops (scan); // Makes sure no options passed.
-
-          if (!ops.file () && !ops.directory ())
-            error () << "either -f|--file or -d|--directory must be specified";
-
-          if (ops.file () && ops.directory ())
-            error () << "both -f|--file and -d|--directory specified";
-
-          if (!scan.more ())
-            error () << "missing path";
-
-          path p (parse_path (scan.next (), sp.wd_path));
-
-          if (scan.more ())
-            error () << "unexpected argument '" << scan.next () << "'";
-
-          try
-          {
-            r = (ops.file () ? file_exists (p) : dir_exists (p)) ? 0 : 1;
-          }
-          catch (const system_error& e)
-          {
-            error () << "cannot test '" << p << "': " << e;
-          }
-        }
-        catch (const invalid_path& e)
-        {
-          error (false)  << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while closing in, out or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 2;
-      }
-
-      // touch [--no-cleanup] [--after <ref-file>] <file>...
-      //
-      // Note that POSIX doesn't specify the behavior for touching an entry
-      // other than file.
-      //
-      // Also note that POSIX doesn't specify if after a file touch failure the
-      // command should proceed with the rest of the arguments. The current
-      // implementation exits immediatelly in such a case.
-      //
-      // Note: can be executed synchronously.
-      //
-      static uint8_t
-      touch (scope& sp,
-             const strings& args,
-             auto_fd in, auto_fd out, auto_fd err) noexcept
-      try
-      {
-        uint8_t r (1);
-        ofdstream cerr (move (err));
-
-        auto error = [&cerr] (bool fail = true)
-        {
-          return error_record (cerr, fail, "touch");
-        };
-
-        try
-        {
-          in.close ();
-          out.close ();
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          touch_options ops (scan);
-
-          auto mtime = [&error] (const path& p) -> timestamp
-          {
-            try
-            {
-              timestamp t (file_mtime (p));
-
-              if (t == timestamp_nonexistent)
-                throw_generic_error (ENOENT);
-
-              return t;
-            }
-            catch (const system_error& e)
-            {
-              error () << "cannot obtain file '" << p
-                       << "' modification time: " << e;
-            }
-            assert (false); // Can't be here.
-            return timestamp ();
-          };
-
-          optional<timestamp> after;
-          if (ops.after_specified ())
-            after = mtime (parse_path (ops.after (), sp.wd_path));
-
-          if (!scan.more ())
-            error () << "missing file";
-
-          // Create files.
-          //
-          while (scan.more ())
-          {
-            path p (parse_path (scan.next (), sp.wd_path));
-
-            try
-            {
-              // Note that we don't register (implicit) cleanup for an
-              // existing path.
-              //
-              if (touch_file (p) && !ops.no_cleanup ())
-                sp.clean ({cleanup_type::always, p}, true /* implicit */);
-
-              if (after)
-              {
-                while (mtime (p) <= *after)
-                  touch_file (p, false /* create */);
-              }
-            }
-            catch (const system_error& e)
-            {
-              error () << "cannot create/update '" << p << "': " << e;
-            }
-          }
-
-          r = 0;
-        }
-        catch (const invalid_path& e)
-        {
-          error (false) << "invalid path '" << e.path << "'";
-        }
-        // Can be thrown while closing in, out or writing to cerr.
-        //
-        catch (const io_error& e)
-        {
-          error (false) << e;
-        }
-        catch (const failed&)
-        {
-          // Diagnostics has already been issued.
-        }
-        catch (const cli::exception& e)
-        {
-          error (false) << e;
-        }
-
-        cerr.close ();
-        return r;
-      }
-      catch (const std::exception&)
-      {
-        return 1;
-      }
-
-      // Run builtin implementation asynchronously.
-      //
-      static builtin
-      async_impl (builtin_impl* fn,
-                  scope& sp,
-                  uint8_t& r,
-                  const strings& args,
-                  auto_fd in, auto_fd out, auto_fd err)
-      {
-        return builtin (
-          r,
-          thread ([fn, &sp, &r, &args,
-                   in  = move (in),
-                   out = move (out),
-                   err = move (err)] () mutable noexcept
-                  {
-                    r = fn (sp, args, move (in), move (out), move (err));
-                  }));
-      }
-
-      template <builtin_impl fn>
-      static builtin
-      async_impl (scope& sp,
-                  uint8_t& r,
-                  const strings& args,
-                  auto_fd in, auto_fd out, auto_fd err)
-      {
-        return async_impl (fn, sp, r, args, move (in), move (out), move (err));
-      }
-
-      // Run builtin implementation synchronously.
-      //
-      template <builtin_impl fn>
-      static builtin
-      sync_impl (scope& sp,
-                 uint8_t& r,
-                 const strings& args,
-                 auto_fd in, auto_fd out, auto_fd err)
-      {
-        r = fn (sp, args, move (in), move (out), move (err));
-        return builtin (r, thread ());
-      }
-
-      const builtin_map builtins
-      {
-        {"cat",   &async_impl<&cat>},
-        {"cp",    &sync_impl<&cp>},
-        {"echo",  &async_impl<&echo>},
-        {"false", &false_},
-        {"ln",    &sync_impl<&ln>},
-        {"mkdir", &sync_impl<&mkdir>},
-        {"mv",    &sync_impl<&mv>},
-        {"rm",    &sync_impl<&rm>},
-        {"rmdir", &sync_impl<&rmdir>},
-        {"sed",   &async_impl<&sed>},
-        {"sleep", &sync_impl<&sleep>},
-        {"test",  &sync_impl<&test>},
-        {"touch", &sync_impl<&touch>},
-        {"true",  &true_}
-      };
-    }
-  }
-}