method

each_byte

v1_8_7_330 - Show latest stable - 0 notes - Class: IO

each_byte() public

Calls the given block once for each byte (0..255) in ios, passing the byte as an argument. The stream must be opened for reading or an IOError will be raised.

f = File.new("testfile")
checksum = 0
f.each_byte {|x| checksum ^= x }   #=> #<File:testfile>
checksum                           #=> 12

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/*
 *  call-seq:
 *     ios.each_byte {|byte| block }  => ios
 *  
 *  Calls the given block once for each byte (0..255) in <em>ios</em>,
 *  passing the byte as an argument. The stream must be opened for
 *  reading or an <code>IOError</code> will be raised.
 *     
 *     f = File.new("testfile")
 *     checksum = 0
 *     f.each_byte {|x| checksum ^= x }   #=> #<File:testfile>
 *     checksum                           #=> 12
 */

static VALUE
rb_io_each_byte(io)
    VALUE io;
{
    rb_io_t *fptr;
    FILE *f;
    int c;

    RETURN_ENUMERATOR(io, 0, 0);
    GetOpenFile(io, fptr);

    for (;;) {
        rb_io_check_readable(fptr);
        f = fptr->f;
        READ_CHECK(f);
        clearerr(f);
        TRAP_BEG;
        c = getc(f);
        TRAP_END;
        if (c == EOF) {
            if (ferror(f)) {
                clearerr(f);
                if (!rb_io_wait_readable(fileno(f)))
                    rb_sys_fail(fptr->path);
                continue;
            }
            break;
        }
        rb_yield(INT2FIX(c & 0xff));
    }
    if (ferror(f)) rb_sys_fail(fptr->path);
    return io;
}

each_byte

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