putchar : write a character (macro)

Synopsis

#include <stdio.h>
int putchar(int ch);
int _putchar_r(void *reent, int ch);
```### Description

putchar is a macro, defined in stdio.h. putchar writes its argument to the standard output stream, after converting it from an int to an unsigned char.

The alternate function _putchar_r is a reentrant version. The extra argument reent is a pointer to a reentrancy structure.### Returns

If successful, putchar returns its argument ch. If an error intervenes, the result is EOF. You can use `ferror(stdin)' to query for errors.

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**Authoritative source**: BUSMASTER DITA help source `putchar.dita`, compiled into `BUSMASTER.CHM` with the application.