Returns true if stat is readable by the real user id of this process.
File.stat("testfile").readable_real? #=> true
If stat is writable by others, returns an integer representing the file permission bits of stat. Returns nil otherwise. The meaning of the bits is platform dependent; on Unix systems, see stat(2).
m = File.stat("/tmp").world_writable? #=> 511 sprintf("%o", m) #=> "777"
Iterates over keys and objects in a weakly referenced object
Make an internal copy of the source buffer. Updates to the copy will not affect the source buffer.
source = IO::Buffer.for("Hello World") # => # #<IO::Buffer 0x00007fd598466830+11 EXTERNAL READONLY SLICE> # 0x00000000 48 65 6c 6c 6f 20 57 6f 72 6c 64 Hello World buffer = source.dup # => # #<IO::Buffer 0x0000558cbec03320+11 INTERNAL> # 0x00000000 48 65 6c 6c 6f 20 57 6f 72 6c 64 Hello World
Read from buffer a value of type at offset. data_type should be one of symbols:
:U8: unsigned integer, 1 byte
:S8: signed integer, 1 byte
:u16: unsigned integer, 2 bytes, little-endian
:U16: unsigned integer, 2 bytes, big-endian
:s16: signed integer, 2 bytes, little-endian
:S16: signed integer, 2 bytes, big-endian
:u32: unsigned integer, 4 bytes, little-endian
:U32: unsigned integer, 4 bytes, big-endian
:s32: signed integer, 4 bytes, little-endian
:S32: signed integer, 4 bytes, big-endian
:u64: unsigned integer, 8 bytes, little-endian
:U64: unsigned integer, 8 bytes, big-endian
:s64: signed integer, 8 bytes, little-endian
:S64: signed integer, 8 bytes, big-endian
:f32: float, 4 bytes, little-endian
:F32: float, 4 bytes, big-endian
:f64: double, 8 bytes, little-endian
:F64: double, 8 bytes, big-endian
A data type refers specifically to the type of binary data that is stored in the buffer. For example, a :u32 data type is a 32-bit unsigned integer in little-endian format.
Example:
string = [1.5].pack('f') # => "\x00\x00\xC0?" IO::Buffer.for(string).get_value(:f32, 0) # => 1.5
Similar to get_value, except that it can handle multiple data types and returns an array of values.
Example:
string = [1.5, 2.5].pack('ff') IO::Buffer.for(string).get_values([:f32, :f32], 0) # => [1.5, 2.5]
Write to a buffer a value of type at offset. type should be one of symbols described in get_value.
buffer = IO::Buffer.new(8) # => # #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL> # 0x00000000 00 00 00 00 00 00 00 00 buffer.set_value(:U8, 1, 111) # => 1 buffer # => # #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL> # 0x00000000 00 6f 00 00 00 00 00 00 .o......
Note that if the type is integer and value is Float, the implicit truncation is performed:
buffer = IO::Buffer.new(8) buffer.set_value(:U32, 0, 2.5) buffer # => # #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL> # 0x00000000 00 00 00 02 00 00 00 00 # ^^ the same as if we'd pass just integer 2
Write values of data_types at offset to the buffer. data_types should be an array of symbols as described in get_value. values should be an array of values to write.
Example:
buffer = IO::Buffer.new(8) buffer.set_values([:U8, :U16], 0, [1, 2]) buffer # => # #<IO::Buffer 0x696f717561746978+8 INTERNAL> # 0x00000000 01 00 02 00 00 00 00 00 ........
Calls superclass method.
If the access mode is :row or :col_or_row, and each argument is either an Integer or a Range, returns rows. Otherwise, returns columns data.
In either case, the returned values are in the order specified by the arguments. Arguments may be repeated.
Returns rows as an Array of CSV::Row objects.
No argument:
source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" table = CSV.parse(source, headers: true) table.values_at # => []
One index:
values = table.values_at(0) values # => [#<CSV::Row "Name":"foo" "Value":"0">]
Two indexes:
values = table.values_at(2, 0) values # => [#<CSV::Row "Name":"baz" "Value":"2">, #<CSV::Row "Name":"foo" "Value":"0">]
One Range:
values = table.values_at(1..2) values # => [#<CSV::Row "Name":"bar" "Value":"1">, #<CSV::Row "Name":"baz" "Value":"2">]
Ranges and indexes:
values = table.values_at(0..1, 1..2, 0, 2) pp values
Output:
[#<CSV::Row "Name":"foo" "Value":"0">, #<CSV::Row "Name":"bar" "Value":"1">, #<CSV::Row "Name":"bar" "Value":"1">, #<CSV::Row "Name":"baz" "Value":"2">, #<CSV::Row "Name":"foo" "Value":"0">, #<CSV::Row "Name":"baz" "Value":"2">]
Returns columns data as row Arrays, each consisting of the specified columns data for that row:
values = table.values_at('Name') values # => [["foo"], ["bar"], ["baz"]] values = table.values_at('Value', 'Name') values # => [["0", "foo"], ["1", "bar"], ["2", "baz"]]