diff options
Diffstat (limited to 'node_modules/fs-extra/docs/fs-read-write.md')
-rw-r--r-- | node_modules/fs-extra/docs/fs-read-write.md | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/node_modules/fs-extra/docs/fs-read-write.md b/node_modules/fs-extra/docs/fs-read-write.md new file mode 100644 index 0000000..805ea3c --- /dev/null +++ b/node_modules/fs-extra/docs/fs-read-write.md @@ -0,0 +1,39 @@ +# About `fs.read()` & `fs.write()` + +[`fs.read()`](https://nodejs.org/api/fs.html#fs_fs_read_fd_buffer_offset_length_position_callback) & [`fs.write()`](https://nodejs.org/api/fs.html#fs_fs_write_fd_buffer_offset_length_position_callback) are different from other `fs` methods in that their callbacks are called with 3 arguments instead of the usual 2 arguments. + +If you're using them with callbacks, they will behave as usual. However, their promise usage is a little different. `fs-extra` promisifies these methods like [`util.promisify()`](https://nodejs.org/api/util.html#util_util_promisify_original) (only available in Node 8+) does. + +Here's the example promise usage: + +## `fs.read()` + +```js +// Basic promises +fs.read(fd, buffer, offset, length, position) + .then(results => { + console.log(results) + // { bytesRead: 20, buffer: <Buffer 0f 34 5d ...> } + }) + +// Async/await usage: +async function example () { + const { bytesRead, buffer } = await fs.read(fd, Buffer.alloc(length), offset, length, position) +} +``` + +## `fs.write()` + +```js +// Basic promises +fs.write(fd, buffer, offset, length, position) + .then(results => { + console.log(results) + // { bytesWritten: 20, buffer: <Buffer 0f 34 5d ...> } + }) + +// Async/await usage: +async function example () { + const { bytesWritten, buffer } = await fs.write(fd, Buffer.alloc(length), offset, length, position) +} +``` |