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# JSON_NO_IO

    #define JSON_NO_IO

When defined, headers `<cstdio>`, `<ios>`, `<iosfwd>`, `<istream>`, and `<ostream>` are not included and parse functions relying on these headers are excluded. This is relevant for environments where these I/O functions are disallowed for security reasons (e.g., Intel Software Guard Extensions (SGX)).

## Default definition

By default, `JSON_NO_IO` is not defined.

    #undef JSON_NO_IO

## Examples

Example

The code below forces the library not to use the headers `<cstdio>`, `<ios>`, `<iosfwd>`, `<istream>`, and `<ostream>`.

    #define JSON_NO_IO 1
    #include <nlohmann/json.hpp>

    ...

## Version history

- Added in version 3.10.0.

Last update: May 17, 2022
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