These pragma directives take header names as parameters at the specified positions:

#pragma include_alias ("header", "header")
#pragma include_alias (<header>, <header>)

Sequences in header names are mapped to source file names verbatim. A backslash '\' is not treated as an escape sequence. See Overview of the preprocessor.

A character constant in a constant expression that controls conditional inclusion matches the value of the same character constant in the execution character set.

A single-character constant may only have a negative value if a plain character (char) is treated as a signed character, see ‑‑char_is_signed.

For information about the search algorithm used for file specifications in angle brackets <>, see Include file search procedure.

For information about the search algorithm used for file specifications enclosed in quotes, see Include file search procedure.

Preprocessing tokens in an #include directive are combined in the same way as outside an #include directive.

There is no explicit nesting limit for #include processing.

# (stringify argument) inserts a \ character in front of a Universal Character Name (UCN) in character constants and string literals.

In addition to the pragma directives described in Pragma directives, the following directives are recognized and will have an indeterminate effect. If a pragma directive is listed both in Pragma directives and here, the information provided in Pragma directives overrides the information here.

The definitions for __TIME__ and __DATE__ are always available.