ARGF

Returns the ARGV array, which contains the arguments passed to your script, one per element.

For example:

$ ruby argf.rb -v glark.txt

ARGF.argv   #=> ["-v", "glark.txt"]

 
               static VALUE
argf_argv(VALUE argf)
{
    return ARGF.argv;
}
            

Puts ARGF into binary mode. Once a stream is in binary mode, it cannot be reset to non-binary mode. This option has the following effects:

• Newline conversion is disabled.

• Encoding conversion is disabled.

• Content is treated as ASCII-8BIT.

 
               static VALUE
argf_binmode_m(VALUE argf)
{
    ARGF.binmode = 1;
    next_argv();
    ARGF_FORWARD(0, 0);
    rb_io_ascii8bit_binmode(ARGF.current_file);
    return argf;
}
            

Returns true if ARGF is being read in binary mode; false otherwise. To enable binary mode use ARGF.binmode.

For example:

ARGF.binmode?  #=> false
ARGF.binmode
ARGF.binmode?  #=> true

 
               static VALUE
argf_binmode_p(VALUE argf)
{
    return ARGF.binmode ? Qtrue : Qfalse;
}
            

This is a deprecated alias for each_byte.

 
               static VALUE
argf_bytes(VALUE argf)
{
    rb_warn("ARGF#bytes is deprecated; use #each_byte instead");
    if (!rb_block_given_p())
        return rb_enumeratorize(argf, ID2SYM(rb_intern("each_byte")), 0, 0);
    return argf_each_byte(argf);
}
            

This is a deprecated alias for each_char.

 
               static VALUE
argf_chars(VALUE argf)
{
    rb_warn("ARGF#chars is deprecated; use #each_char instead");
    if (!rb_block_given_p())
        return rb_enumeratorize(argf, ID2SYM(rb_intern("each_char")), 0, 0);
    return argf_each_char(argf);
}
            

Closes the current file and skips to the next file in ARGV. If there are no more files to open, just closes the current file. STDIN will not be closed.

For example:

$ ruby argf.rb foo bar

ARGF.filename  #=> "foo"
ARGF.close
ARGF.filename  #=> "bar"
ARGF.close

 
               static VALUE
argf_close_m(VALUE argf)
{
    next_argv();
    argf_close(argf);
    if (ARGF.next_p != -1) {
        ARGF.next_p = 1;
    }
    ARGF.lineno = 0;
    return argf;
}
            

Returns true if the current file has been closed; false otherwise. Use ARGF.close to actually close the current file.

 
               static VALUE
argf_closed(VALUE argf)
{
    next_argv();
    ARGF_FORWARD(0, 0);
    return rb_io_closed(ARGF.current_file);
}
            

This is a deprecated alias for each_codepoint.

 
               static VALUE
argf_codepoints(VALUE argf)
{
    rb_warn("ARGF#codepoints is deprecated; use #each_codepoint instead");
    if (!rb_block_given_p())
        return rb_enumeratorize(argf, ID2SYM(rb_intern("each_codepoint")), 0, 0);
    return argf_each_codepoint(argf);
}
            

Returns an enumerator which iterates over each line (separated by sep, which defaults to your platform's newline character) of each file in ARGV. If a block is supplied, each line in turn will be yielded to the block, otherwise an enumerator is returned. The optional limit argument is an Integer specifying the maximum length of each line; longer lines will be split according to this limit.

This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last line of the first file has been returned, the first line of the second file is returned. The ARGF.filename and ARGF.lineno methods can be used to determine the filename and line number, respectively, of the current line.

For example, the following code prints out each line of each named file prefixed with its line number, displaying the filename once per file:

ARGF.each_line do |line|
  puts ARGF.filename if ARGF.lineno == 1
  puts "#{ARGF.lineno}: #{line}"
end

 
               static VALUE
argf_each_line(int argc, VALUE *argv, VALUE argf)
{
    RETURN_ENUMERATOR(argf, argc, argv);
    FOREACH_ARGF() {
        argf_block_call_line(rb_intern("each_line"), argc, argv, argf);
    }
    return argf;
}
            

Iterates over each byte of each file in ARGV. A byte is returned as an Integer in the range 0..255.

This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last byte of the first file has been returned, the first byte of the second file is returned. The ARGF.filename method can be used to determine the filename of the current byte.

If no block is given, an enumerator is returned instead.

For example:

ARGF.bytes.to_a  #=> [35, 32, ... 95, 10]

 
               static VALUE
argf_each_byte(VALUE argf)
{
    RETURN_ENUMERATOR(argf, 0, 0);
    FOREACH_ARGF() {
        argf_block_call(rb_intern("each_byte"), 0, 0, argf);
    }
    return argf;
}
            

Iterates over each character of each file in ARGF.

This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last character of the first file has been returned, the first character of the second file is returned. The ARGF.filename method can be used to determine the name of the file in which the current character appears.

If no block is given, an enumerator is returned instead.

 
               static VALUE
argf_each_char(VALUE argf)
{
    RETURN_ENUMERATOR(argf, 0, 0);
    FOREACH_ARGF() {
        argf_block_call(rb_intern("each_char"), 0, 0, argf);
    }
    return argf;
}
            

Iterates over each codepoint of each file in ARGF.

This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last codepoint of the first file has been returned, the first codepoint of the second file is returned. The ARGF.filename method can be used to determine the name of the file in which the current codepoint appears.

If no block is given, an enumerator is returned instead.

 
               static VALUE
argf_each_codepoint(VALUE argf)
{
    RETURN_ENUMERATOR(argf, 0, 0);
    FOREACH_ARGF() {
        argf_block_call(rb_intern("each_codepoint"), 0, 0, argf);
    }
    return argf;
}
            

Returns an enumerator which iterates over each line (separated by sep, which defaults to your platform's newline character) of each file in ARGV. If a block is supplied, each line in turn will be yielded to the block, otherwise an enumerator is returned. The optional limit argument is an Integer specifying the maximum length of each line; longer lines will be split according to this limit.

This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last line of the first file has been returned, the first line of the second file is returned. The ARGF.filename and ARGF.lineno methods can be used to determine the filename and line number, respectively, of the current line.

For example, the following code prints out each line of each named file prefixed with its line number, displaying the filename once per file:

ARGF.each_line do |line|
  puts ARGF.filename if ARGF.lineno == 1
  puts "#{ARGF.lineno}: #{line}"
end

 
               static VALUE
argf_each_line(int argc, VALUE *argv, VALUE argf)
{
    RETURN_ENUMERATOR(argf, argc, argv);
    FOREACH_ARGF() {
        argf_block_call_line(rb_intern("each_line"), argc, argv, argf);
    }
    return argf;
}
            

Returns true if the current file in ARGF is at end of file, i.e. it has no data to read. The stream must be opened for reading or an IOError will be raised.

$ echo "eof" | ruby argf.rb

ARGF.eof?                 #=> false
3.times { ARGF.readchar }
ARGF.eof?                 #=> false
ARGF.readchar             #=> "\n"
ARGF.eof?                 #=> true

 
               static VALUE
argf_eof(VALUE argf)
{
    next_argv();
    if (RTEST(ARGF.current_file)) {
        if (ARGF.init_p == 0) return Qtrue;
        next_argv();
        ARGF_FORWARD(0, 0);
        if (rb_io_eof(ARGF.current_file)) {
            return Qtrue;
        }
    }
    return Qfalse;
}
            

Returns true if the current file in ARGF is at end of file, i.e. it has no data to read. The stream must be opened for reading or an IOError will be raised.

$ echo "eof" | ruby argf.rb

ARGF.eof?                 #=> false
3.times { ARGF.readchar }
ARGF.eof?                 #=> false
ARGF.readchar             #=> "\n"
ARGF.eof?                 #=> true

 
               static VALUE
argf_eof(VALUE argf)
{
    next_argv();
    if (RTEST(ARGF.current_file)) {
        if (ARGF.init_p == 0) return Qtrue;
        next_argv();
        ARGF_FORWARD(0, 0);
        if (rb_io_eof(ARGF.current_file)) {
            return Qtrue;
        }
    }
    return Qfalse;
}
            

Returns the external encoding for files read from ARGF as an Encoding object. The external encoding is the encoding of the text as stored in a file. Contrast with ARGF.internal_encoding, which is the encoding used to represent this text within Ruby.

To set the external encoding use ARGF.set_encoding.

For example:

ARGF.external_encoding  #=>  #<Encoding:UTF-8>

 
               static VALUE
argf_external_encoding(VALUE argf)
{
    if (!RTEST(ARGF.current_file)) {
        return rb_enc_from_encoding(rb_default_external_encoding());
    }
    return rb_io_external_encoding(rb_io_check_io(ARGF.current_file));
}
            

Returns the current file as an IO or File object. $stdin is returned when the current file is STDIN.

For example:

$ echo "foo" > foo
$ echo "bar" > bar

$ ruby argf.rb foo bar

ARGF.file      #=> #<File:foo>
ARGF.read(5)   #=> "foo\nb"
ARGF.file      #=> #<File:bar>

 
               static VALUE
argf_file(VALUE argf)
{
    next_argv();
    return ARGF.current_file;
}
            

Returns the current filename. “-” is returned when the current file is STDIN.

For example:

$ echo "foo" > foo
$ echo "bar" > bar
$ echo "glark" > glark

$ ruby argf.rb foo bar glark

ARGF.filename  #=> "foo"
ARGF.read(5)   #=> "foo\nb"
ARGF.filename  #=> "bar"
ARGF.skip
ARGF.filename  #=> "glark"

 
               static VALUE
argf_filename(VALUE argf)
{
    next_argv();
    return ARGF.filename;
}
            

Returns an integer representing the numeric file descriptor for the current file. Raises an ArgumentError if there isn't a current file.

ARGF.fileno    #=> 3

 
               static VALUE
argf_fileno(VALUE argf)
{
    if (!next_argv()) {
        rb_raise(rb_eArgError, "no stream");
    }
    ARGF_FORWARD(0, 0);
    return rb_io_fileno(ARGF.current_file);
}
            

Gets the next 8-bit byte (0..255) from ARGF. Returns nil if called at the end of the stream.

For example:

$ echo "foo" > file
$ ruby argf.rb file

ARGF.getbyte #=> 102
ARGF.getbyte #=> 111
ARGF.getbyte #=> 111
ARGF.getbyte #=> 10
ARGF.getbyte #=> nil

 
               static VALUE
argf_getbyte(VALUE argf)
{
    VALUE ch;

  retry:
    if (!next_argv()) return Qnil;
    if (!RB_TYPE_P(ARGF.current_file, T_FILE)) {
        ch = rb_funcall3(ARGF.current_file, rb_intern("getbyte"), 0, 0);
    }
    else {
        ch = rb_io_getbyte(ARGF.current_file);
    }
    if (NIL_P(ch) && ARGF.next_p != -1) {
        argf_close(argf);
        ARGF.next_p = 1;
        goto retry;
    }

    return ch;
}
            

Reads the next character from ARGF and returns it as a String. Returns nil at the end of the stream.

ARGF treats the files named on the command line as a single file created by concatenating their contents. After returning the last character of the first file, it returns the first character of the second file, and so on.

For example:

$ echo "foo" > file
$ ruby argf.rb file

ARGF.getc  #=> "f"
ARGF.getc  #=> "o"
ARGF.getc  #=> "o"
ARGF.getc  #=> "\n"
ARGF.getc  #=> nil
ARGF.getc  #=> nil

 
               static VALUE
argf_getc(VALUE argf)
{
    VALUE ch;

  retry:
    if (!next_argv()) return Qnil;
    if (ARGF_GENERIC_INPUT_P()) {
        ch = rb_funcall3(ARGF.current_file, rb_intern("getc"), 0, 0);
    }
    else {
        ch = rb_io_getc(ARGF.current_file);
    }
    if (NIL_P(ch) && ARGF.next_p != -1) {
        argf_close(argf);
        ARGF.next_p = 1;
        goto retry;
    }

    return ch;
}
            

Returns the next line from the current file in ARGF.

By default lines are assumed to be separated by $/; to use a different character as a separator, supply it as a String for the sep argument.

The optional limit argument specifies how many characters of each line to return. By default all characters are returned.

See IO.readlines for details about getline_args.

 
               static VALUE
argf_gets(int argc, VALUE *argv, VALUE argf)
{
    VALUE line;

    line = argf_getline(argc, argv, argf);
    rb_lastline_set(line);

    return line;
}
            

Returns the file extension appended to the names of modified files under in-place edit mode. This value can be set using ARGF.inplace_mode= or passing the -i switch to the Ruby binary.

 
               static VALUE
argf_inplace_mode_get(VALUE argf)
{
    if (!ARGF.inplace) return Qnil;
    if (NIL_P(ARGF.inplace)) return rb_str_new(0, 0);
    return rb_str_dup(ARGF.inplace);
}
            

Sets the filename extension for in-place editing mode to the given String. Each file being edited has this value appended to its filename. The modified file is saved under this new name.

For example:

$ ruby argf.rb file.txt

ARGF.inplace_mode = '.bak'
ARGF.each_line do |line|
  print line.sub("foo","bar")
end

Each line of file.txt has the first occurrence of “foo” replaced with “bar”, then the new line is written out to file.txt.bak.

 
               static VALUE
argf_inplace_mode_set(VALUE argf, VALUE val)
{
    if (rb_safe_level() >= 1 && OBJ_TAINTED(val))
        rb_insecure_operation();

    if (!RTEST(val)) {
        ARGF.inplace = Qfalse;
    }
    else if (StringValueCStr(val), !RSTRING_LEN(val)) {
        ARGF.inplace = Qnil;
    }
    else {
        ARGF.inplace = rb_str_new_frozen(val);
    }
    return argf;
}
            

Returns the internal encoding for strings read from ARGF as an Encoding object.

If ARGF.set_encoding has been called with two encoding names, the second is returned. Otherwise, if Encoding.default_external has been set, that value is returned. Failing that, if a default external encoding was specified on the command-line, that value is used. If the encoding is unknown, nil is returned.

 
               static VALUE
argf_internal_encoding(VALUE argf)
{
    if (!RTEST(ARGF.current_file)) {
        return rb_enc_from_encoding(rb_default_external_encoding());
    }
    return rb_io_internal_encoding(rb_io_check_io(ARGF.current_file));
}
            

Returns the current line number of ARGF as a whole. This value can be set manually with ARGF.lineno=.

For example:

ARGF.lineno   #=> 0
ARGF.readline #=> "This is line 1\n"
ARGF.lineno   #=> 1

 
               static VALUE
argf_lineno(VALUE argf)
{
    return INT2FIX(ARGF.lineno);
}