# OS_TWarning

## Syntax

  `#include <nitro/os.h>`
  `void OS_TWarning( const char *fmt, ... );`

## Arguments

fmt | Output format string.
... | Variable number of arguments

## Return Values

None.

## Description

Outputs a string. Internally, this function calls `OS_VSNPrintf`. Therefore, the usable string format (string output format) is more restricted than `OS_Warning()`. However, you can save on the code and stack overhead by using this function instead of `OS_VSNPrintf()` or `OS_Warning()`.

The output format is:

`<filename>:<linenumber>` Warning: <string>

The filename and line number described by this `OS_TWarning` function are indicated by `<filename>` and `<linenumber>`. `<string>` is created from `fmt` and the variable number of arguments.

The maximum string length that can be displayed is 255 characters. If a string with 256 or more characters is specified, all characters from the 256th character are ignored.

This function is used for debugging. It will not be generated in the final ROM version (`FINALROM`).

## Internal Operation

`OS_Warning()` is actually a `#define` of `OSi_Warning()`. `OSi_Warning()` is compiled with weak symbols. Therefore you can overwrite them with your own function definitions.

## See Also

`OS_TPrintf`
`OS_TPanic`

## Revision History

2009/10/02 Explained the maximum displayable string length.
2004/11/25 Added a description of the weak symbol.
2004/09/10 Initial version.

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