5.14.3.11 The #pragma smart_io_format Directive

The #pragma smart_io_format directive notifies the compiler that the listed specifications are used by smart IO functions in the current module and that the IO library code linked in must be able to process them. The pragma is functionally similar to the -msmart-io-format option (see Smart-io-format Option) but can be applied in source code and in multiple modules.

The smart_io_format pragma has the general form:

#pragma smart_io_format "fmt"

where "fmt" is a string containing one or more formatted, printf-style conversion specifications, following the same requirements as the argument to the -msmart-io-format option.

Only one pragma is relevant per translation module. If more than one is present, the last takes precedence. The placeholders indicated by the pragmas are collated across all modules, however, and this accumulation indicates the features required by IO functions whose usage information cannot be determined from either the format strings or the arguments.

Usage of this pragma will supersede any usage of the -msmart-io-format option, but only for the module in which it appears.