fgetc, getc

From cppreference.com
< c ‎ | io
Defined in header <stdio.h>
int fgetc ( FILE * stream ) ;
(1)
int getc ( FILE * stream ) ;
(2)
1) Reads the next character from the given input stream.
2) Same as fgetc , except that if getc is implemented as a macro, it may evaluate stream more than once, so the corresponding argument should never be an expression with side effects.

Parameters

stream - to read the character from

Return value

On success, returns the obtained character as an unsigned char converted to an int . On failure, returns EOF .

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

Example

#include <stdio.h>
#include <stdlib.h>
 
int main(void)
{
    const char* fname = "/tmp/unique_name.txt"; // or tmpnam(NULL);
    int is_ok = EXIT_FAILURE;
 
    FILE* fp = fopen(fname, "w+");
    if (!fp) {
        perror("File opening failed");
        return is_ok;
    }
    fputs("Hello, world!\n", fp);
    rewind(fp);
 
    int c; // note: int, not char, required to handle EOF
    while ((c = fgetc(fp)) != EOF) // standard C I/O file reading loop
        putchar(c);
 
    if (ferror(fp))
        puts("I/O error when reading");
    else if (feof(fp)) {
        puts("End of file is reached successfully");
        is_ok = EXIT_SUCCESS;
    }
 
    fclose(fp);
    remove(fname);
    return is_ok;
}

Possible output:

Hello, world!
End of file is reached successfully

References

  • C23 standard (ISO/IEC 9899:2024):
  • 7.21.7.1 The fgetc function (p: TBD)
  • 7.21.7.5 The getc function (p: TBD)
  • C17 standard (ISO/IEC 9899:2018):
  • 7.21.7.1 The fgetc function (p: 240-241)
  • 7.21.7.5 The getc function (p: 242)
  • C11 standard (ISO/IEC 9899:2011):
  • 7.21.7.1 The fgetc function (p: 330)
  • 7.21.7.5 The getc function (p: 332)
  • C99 standard (ISO/IEC 9899:1999):
  • 7.19.7.1 The fgetc function (p: 296)
  • 7.19.7.5 The getc function (p: 297-298)
  • C89/C90 standard (ISO/IEC 9899:1990):
  • 4.9.7.1 The fgetc function
  • 4.9.7.5 The getc function

See also

reads a character from stdin
(function)
(removed in C11) (C11)
reads a character string from stdin
(function)
writes a character to a file stream
(function)
puts a character back into a file stream
(function)
C++ documentation for fgetc , getc