| Defined in header <stdio.h> | ||
|---|---|---|
| int putchar( int ch ); | 
Writes a character ch to stdout. Internally, the character is converted to unsigned char just before being written.
Equivalent to putc(ch, stdout).
| ch | - | character to be written | 
On success, returns the written character.
On failure, returns EOF and sets the error indicator (see ferror()) on stdout.
Shows putchar with error checking
#include <stdio.h>
#include <stdlib.h>
 
int main(void)
{
    int ret_code = 0;
    for (char c = 'a'; (ret_code != EOF) && (c != 'z'); c++)
        ret_code = putchar(c);
 
    // Test whether EOF was reached.
    if (ret_code == EOF && ferror(stdout))
    {
        fprintf(stderr, "putchar() failed in file %s at line # %d\n",
                __FILE__, __LINE__ - 6);
        perror("putchar()");
        exit(EXIT_FAILURE);
    }
    putchar('\n');
 
    // putchar return value is not equal to the argument
    int r = 0x1070;
    printf("\n0x%x\n", r);
    r = putchar(r);
    printf("\n0x%x\n", r);
}Output:
abcdefghijklmnopqrstuvwxy 0x1070 p 0x70
| writes a character to a file stream (function) | |
| C++ documentation for putchar | |
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Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
    https://en.cppreference.com/w/c/io/putchar