read.md

read

Read data from file associated with fd file descriptor into buffer buf. Up to size of the buf.length will be read, or less.

read(fd: number, buf: Buffer): number;

• fd - file descriptor
• buf - Buffer where to place read data

Returns a number which is the actual bytes read into the buffer, if negative, represents an error. If zero, represents end-of-file, but if buf is of length zero than zero does not necessarily mean end-of-file.

See readAsync for asynchronous variant.

Example

require('libsys/shim');
const libjs = require('libjs');

const O_RDONLY = 0;
const fd = libjs.open(__filename, O_RDONLY);

if(fd > -1) {
    const buf = new Buffer(1024);
    const bytes_read = libjs.read(fd, buf);

    console.log('Bytes read: ', bytes_read);
    console.log(buf.toString().substr(0, bytes_read));
} else {
    console.log('Error: ', fd);
}