std::getchar

 

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File access fopen freopen fclose fflush fwide setbuf setvbuf Direct input/output fread fwrite Unformatted input/output fgetcgetc fgets fputcputc fputs getchar gets (until C++14) putchar puts ungetc fgetwcgetwc fgetws fputwcputwc fputws getwchar putwchar ungetwc Formatted input scanffscanfsscanf vscanfvfscanfvsscanf (C++11)(C++11)(C++11)     wscanffwscanfswscanf vwscanfvfwscanfvswscanf (C++11)(C++11)(C++11)	Formatted output printffprintfsprintfsnprintf (C++11) vprintfvfprintfvsprintfvsnprintf (C++11)     wprintffwprintfswprintf vwprintfvfwprintfvswprintf File positioning ftell fgetpos fseek fsetpos rewind Error handling clearerr feof ferror perror Operations on files remove rename tmpfile tmpnam

 

Defined in header <cstdio>
int getchar();

Reads the next character from stdin.

Equivalent to std::getc(stdin).

Parameters

(none)

Return value

The obtained character on success or EOF on failure.

If the failure has been caused by end of file condition, additionally sets the eof indicator (see std::feof()) on stdin. If the failure has been caused by some other error, sets the error indicator (see std::ferror()) on stdin.

Example

std::getchar with error checking. Exit program by entering ESC char.

#include <cctype>
#include <cstdio>
#include <cstdlib>
#include <iomanip>
#include <iostream>
 
int main()
{
    for (int ch; (ch = std::getchar()) != EOF ;) // read/print "abc" from stdin
    {
        if (std::isprint(ch))
            std::cout << static_cast<char>(ch) << '\n';
        if (ch == 27) // 'ESC' (escape) in ASCII
            return EXIT_SUCCESS;
    }
 
    // Test reason for reaching EOF.
    if (std::feof(stdin)) // if failure caused by end-of-file condition
        std::cout << "End of file reached\n";
    else if (std::ferror(stdin)) // if failure caused by some other error
    {
        std::perror("getchar()");
        std::cerr << "getchar() failed in file " << std::quoted(__FILE__)
                  << " at line # " << __LINE__ - 14 << '\n';
        std::exit(EXIT_FAILURE);
    }
 
    return EXIT_SUCCESS;
}

Possible output:

abc
a
b
c
^[

See also

fgetcgetc	gets a character from a file stream (function)
C documentation for getchar