.. _putchar:
.. _getchar:

getchar() and putchar()
=======================

.. function:: getchar

.. function:: putchar

In addition to :ref:`scanf` and :ref:`printf`, two additional input-output
functions that are useful in some situations are :func:`getchar` and
:func:`putchar`.

Since :keyword:`char` values are stored as an :keyword:`int`,
:func:`getchar` returns an :keyword:`int`\ .

Here is an example that can read the standard input and write all
capital letters to the standard output. The reason for calling
``fflush(stdout);`` is to force any characters that are still on the
output buffer to display immediately.

::

    #include <stdio.h>
    
    int main(void)
    {
        int c;
    
        while((c = getchar()) != EOF )
            putchar(toupper(c));
    
        fflush(stdout);
        return 0;
    }

.. _fgetc:
.. _fputc:

fgetc() and fputc()
=======================

.. function:: fgetc

.. function:: fputc


:func:`fgetc` and :func:`fputc`, work the same as :func:`getchar` and
:func:`putchar` except they take an extra argument for an open file descriptor.

::

    #include <stdio.h>
    
    int main(void)
    {
        FILE *rfp, *wfp;
        int c;

        if ((rfp = fopen("fileToRead", "r")) == NULL) {
            printf("Cannot open file to read");
            return 1;
        }
        if ((wfp = fopen("fileToWrite", "w")) == NULL) {
            printf("Cannot open file to write");
            return 1;
        }

        while((c = fgetc(rfp)) != EOF)
            fputc(c, wfp);

        fclose(rfp);
        fflush(wfp);
        fclose(wfp);
    }