< cpp‎ | io
Defined in header <print>
void vprint_nonunicode( std::FILE* stream,
                        std::string_view fmt, std::format_args args );
(1) (since C++23)
void vprint_nonunicode( std::string_view fmt, std::format_args args );
(2) (since C++23)

Format args according to the format string fmt, and writes the result to the stream.

1) Writes the result of std::vformat(fmt, args) to the stream. The behavior is undefined if stream is not a valid pointer to a C stream.
2) same as (1) when stream is equal to the standard C output stream stdout, i.e. std::vprint_nonunicode(stdout, fmt, args);.


[edit] Parameters

stream - output file stream to write to
fmt - an object that represents the format string. The format string consists of
  • ordinary characters (except { and }), which are copied unchanged to the output,
  • escape sequences {{ and }}, which are replaced with { and } respectively in the output, and
  • replacement fields.

Each replacement field has the following format:

{ arg-id (optional) } (1)
{ arg-id (optional) : format-spec } (2)
1) replacement field without a format specification
2) replacement field with a format specification
arg-id - specifies the index of the argument in args whose value is to be used for formatting; if it is omitted, the arguments are used in order.

The arg-id s in a format string must all be present or all be omitted. Mixing manual and automatic indexing is an error.

format-spec - the format specification defined by the std::formatter specialization for the corresponding argument. Cannot start with }.

(since C++23)
(since C++26)
  • For other formattable types, the format specification is determined by user-defined formatter specializations.
args - arguments to be formatted

[edit] Return value


[edit] Exceptions

[edit] Notes

Feature-test macro Value Std Feature
__cpp_lib_print 202207L (C++23) Formatted output
__cpp_lib_format 202207L (C++23) Exposing std::basic_format_string

[edit] Example

[edit] See also

prints to Unicode capable stdout or a file stream using type-erased argument representation
(function) [edit]
outputs character data using type-erased argument representation
(function) [edit]
prints to stdout or a file stream using formatted representation of the arguments
(function template) [edit]
stores formatted representation of the arguments in a new string
(function template) [edit]