intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 32 insertions, 0 deletions

diff --git a/util/system/env.h b/util/system/env.h
new file mode 100644
index 0000000000..e2ccdd1e95
--- /dev/null
+++ b/util/system/env.h
@@ -0,0 +1,32 @@
+#pragma once
+
+#include <util/generic/string.h>
+
+/**
+ * Search the environment list provided by the host environment for associated variable.
+ *
+ * @param key   String identifying the name of the environmental variable to look for
+ * @param def   String that returns if environmental variable not found by key
+ *
+ * @return      String that is associated with the matched environment variable or empty string if
+ *              such variable is missing.
+ *
+ * @note        Use it only in pair with `SetEnv` as there may be inconsistency in their behaviour
+ *              otherwise.
+ * @note        Calls to `GetEnv` and `SetEnv` from different threads must be synchronized.
+ * @see         SetEnv
+ */
+TString GetEnv(const TString& key, const TString& def = TString());
+
+/**
+ * Add or change environment variable provided by the host environment.
+ *
+ * @key         String identifying the name of the environment variable to set or change
+ * @value       Value to assign
+
+ * @note        Use it only in pair with `GetEnv` as there may be inconsistency in their behaviour
+ *              otherwise.
+ * @note        Calls to `GetEnv` and `SetEnv` from different threads must be synchronized.
+ * @see         GetEnv
+ */
+void SetEnv(const TString& key, const TString& value);