Reference/read0
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read0 (file read function)
Read file
read0 file
The read0 function reads a text file, returning a list of lines. Lines are assumed delimited by either LF or CRLF, and the delimiters are removed.
Example
q)`:test.txt 0:("hello";"goodbye") / write some text to a file
q)read0`:test.txt
("hello";"goodbye")
q)d:raze{read0(`:/tmp/data;x;100000)}each 100000*til 5 / read 500000 lines, chunks of (up to) 100000 at a time
Read line
read0 handle
The read0 function can read a line of text from a handle, or from the console.
Example
q)rl:{1">> ";read0 0}
q)rl`
>> xiskso
"xiskso"
Read bytes
read0 (file; offset; length)
The read0 function can read bytes from a file.
q)`:foo 0: enlist "hello world" q)read0 (`:foo;6;5) "world"
Starting with KDB+ 3.4 2016.05.31 read0 allows user to specify how many bytes to read from a fifo.
q)h:hopen`$":fifo:///etc/redhat-release" q)read0(h;8) "Red Hat " q)read0(h;8) "Enterpri"
See also
For a complete list of functions, see the kdb+ Function Reference.
