Flowdock
method

read

Importance_2
Ruby latest stable (v1_9_3_392) - 0 notes - Class: ARGF
read(p1 = v1, p2 = v2) public

Reads length bytes from ARGF. The files named on the command line are concatenated and treated as a single file by this method, so when called without arguments the contents of this pseudo file are returned in their entirety.

length must be a non-negative integer or nil. If it is a positive integer, read tries to read at most length bytes. It returns nil if an EOF was encountered before anything could be read. Fewer than length bytes may be returned if an EOF is encountered during the read.

If length is omitted or is nil, it reads until EOF. A String is returned even if EOF is encountered before any data is read.

If length is zero, it returns _“”_.

If the optional buffer argument is present, it must reference a String, which will receive the data.

For example:

$ echo "small" > small.txt
$ echo "large" > large.txt
$ ./glark.rb small.txt large.txt

ARGF.read      #=> "small\nlarge"
ARGF.read(200) #=> "small\nlarge"
ARGF.read(2)   #=> "sm"
ARGF.read(0)   #=> ""

Note that this method behaves like fread() function in C. If you need the behavior like read(2) system call, consider ARGF.readpartial.

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