Single ~ uses g_get_home_dir() that honor HOME environment variable.
However, ~user always consult the passwd file.
* not expanded char. If no expansion pattern was found, the first char is
* appended to given GString.
*
+ * Please note that for a single ~, g_get_home_dir() is used and if a valid
+ * HOME environment variable is set it is preferred than passwd file.
+ * However, for ~user expansion the passwd file is always used.
+ *
* @input: String pointer with the content to be parsed.
* @str: GString that will be filled with expanded content.
* @flags Flags that determine which expansion are processed.