thedesk/app/node_modules/fstream/README.md

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2018-02-18 18:29:06 +11:00
Like FS streams, but with stat on them, and supporting directories and
symbolic links, as well as normal files. Also, you can use this to set
the stats on a file, even if you don't change its contents, or to create
a symlink, etc.
So, for example, you can "write" a directory, and it'll call `mkdir`. You
can specify a uid and gid, and it'll call `chown`. You can specify a
`mtime` and `atime`, and it'll call `utimes`. You can call it a symlink
and provide a `linkpath` and it'll call `symlink`.
Note that it won't automatically resolve symbolic links. So, if you
call `fstream.Reader('/some/symlink')` then you'll get an object
that stats and then ends immediately (since it has no data). To follow
symbolic links, do this: `fstream.Reader({path:'/some/symlink', follow:
true })`.
There are various checks to make sure that the bytes emitted are the
same as the intended size, if the size is set.
## Examples
```javascript
fstream
.Writer({ path: "path/to/file"
, mode: 0755
, size: 6
})
.write("hello\n")
.end()
```
This will create the directories if they're missing, and then write
`hello\n` into the file, chmod it to 0755, and assert that 6 bytes have
been written when it's done.
```javascript
fstream
.Writer({ path: "path/to/file"
, mode: 0755
, size: 6
, flags: "a"
})
.write("hello\n")
.end()
```
You can pass flags in, if you want to append to a file.
```javascript
fstream
.Writer({ path: "path/to/symlink"
, linkpath: "./file"
, SymbolicLink: true
, mode: "0755" // octal strings supported
})
.end()
```
If isSymbolicLink is a function, it'll be called, and if it returns
true, then it'll treat it as a symlink. If it's not a function, then
any truish value will make a symlink, or you can set `type:
'SymbolicLink'`, which does the same thing.
Note that the linkpath is relative to the symbolic link location, not
the parent dir or cwd.
```javascript
fstream
.Reader("path/to/dir")
.pipe(fstream.Writer("path/to/other/dir"))
```
This will do like `cp -Rp path/to/dir path/to/other/dir`. If the other
dir exists and isn't a directory, then it'll emit an error. It'll also
set the uid, gid, mode, etc. to be identical. In this way, it's more
like `rsync -a` than simply a copy.