1 files changed, 50 insertions, 0 deletions
diff --git a/libbutl/process-io.hxx b/libbutl/process-io.hxx
new file mode 100644
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+++ b/libbutl/process-io.hxx
@@ -0,0 +1,50 @@
+// file      : libbutl/process-io.hxx -*- C++ -*-
+// license   : MIT; see accompanying LICENSE file
+
+#pragma once
+
+#include <ostream>
+
+#include <libbutl/process.hxx>
+
+#include <libbutl/export.hxx>
+
+namespace butl
+{
+  inline std::ostream&
+  operator<< (std::ostream& o, const process_path& p)
+  {
+    return o << p.recall_string ();
+  }
+
+  inline std::ostream&
+  operator<< (std::ostream& o, const process_args& a)
+  {
+    process::print (o, a.argv, a.argc);
+    return o;
+  }
+
+  // Print the environment variables and the current working directory (if
+  // specified) in a POSIX shell command line notation. The process path
+  // itself is not printed. For example:
+  //
+  // LC_ALL=C
+  //
+  // If an environment variable is in the `name` rather than in the
+  // `name=value` form, then it is considered unset. Since there is no POSIX
+  // way to unset a variable on the command line, this information is printed
+  // as `name=` (ambiguous with assigning an empty value but the two cases are
+  // normally handled in the same way). For example:
+  //
+  // PATH= LC_ALL=C
+  //
+  // Note that since there is no POSIX way to change the current working
+  // directory of a command to be executed, this information is printed in a
+  // pseudo-notation by assigning to PWD (which, according POSIX, would result
+  // in the undefined behavior of the cwd utility). For example:
+  //
+  // PWD=/tmp LC_ALL=C
+  //
+  LIBBUTL_SYMEXPORT std::ostream&
+  operator<< (std::ostream&, const process_env&);
+}