C Programming/stdio.h/putchar
putchar is a function in the C programming language that writes a single character to the standard output stream, stdout.[1] Its prototype is as follows:
int putchar (int character)
The character to be printed is fed into the function as an argument, and if the writing is successful, the argument character is returned. Otherwise, end-of-file is returned.
The putchar
function is specified in the C standard library header file stdio.h.
Sample usage
[edit | edit source]The following program uses getchar
to read characters into an array and print them out using the putchar
function after an end-of-file character is found.
#include <stdio.h>
int main(void)
{
char str[1000];
int ch, i, n = 0;
while ((ch = getchar()) != EOF && n < 1000)
str[n++] = ch;
for (i = 0; i < n; ++i)
putchar(str[i]);
putchar('\n'); /* trailing '\n' needed in Standard C */
return 0;
}
The program specifies the reading length's maximum value at 1000 characters. It will stop reading either after reading 1000 characters or after reading in an end-of-file indicator, whichever comes first.
References
[edit | edit source]- ↑ ISO/IEC 9899:1999 specification (PDF). p. 299, § 7.19.7.9.