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diff --git a/node_modules/graceful-fs/README.md b/node_modules/graceful-fs/README.md new file mode 100644 index 0000000..5273a50 --- /dev/null +++ b/node_modules/graceful-fs/README.md @@ -0,0 +1,133 @@ +# graceful-fs + +graceful-fs functions as a drop-in replacement for the fs module, +making various improvements. + +The improvements are meant to normalize behavior across different +platforms and environments, and to make filesystem access more +resilient to errors. + +## Improvements over [fs module](https://nodejs.org/api/fs.html) + +* Queues up `open` and `readdir` calls, and retries them once + something closes if there is an EMFILE error from too many file + descriptors. +* fixes `lchmod` for Node versions prior to 0.6.2. +* implements `fs.lutimes` if possible. Otherwise it becomes a noop. +* ignores `EINVAL` and `EPERM` errors in `chown`, `fchown` or + `lchown` if the user isn't root. +* makes `lchmod` and `lchown` become noops, if not available. +* retries reading a file if `read` results in EAGAIN error. + +On Windows, it retries renaming a file for up to one second if `EACCESS` +or `EPERM` error occurs, likely because antivirus software has locked +the directory. + +## USAGE + +```javascript +// use just like fs +var fs = require('graceful-fs') + +// now go and do stuff with it... +fs.readFileSync('some-file-or-whatever') +``` + +## Global Patching + +If you want to patch the global fs module (or any other fs-like +module) you can do this: + +```javascript +// Make sure to read the caveat below. +var realFs = require('fs') +var gracefulFs = require('graceful-fs') +gracefulFs.gracefulify(realFs) +``` + +This should only ever be done at the top-level application layer, in +order to delay on EMFILE errors from any fs-using dependencies. You +should **not** do this in a library, because it can cause unexpected +delays in other parts of the program. + +## Changes + +This module is fairly stable at this point, and used by a lot of +things. That being said, because it implements a subtle behavior +change in a core part of the node API, even modest changes can be +extremely breaking, and the versioning is thus biased towards +bumping the major when in doubt. + +The main change between major versions has been switching between +providing a fully-patched `fs` module vs monkey-patching the node core +builtin, and the approach by which a non-monkey-patched `fs` was +created. + +The goal is to trade `EMFILE` errors for slower fs operations. So, if +you try to open a zillion files, rather than crashing, `open` +operations will be queued up and wait for something else to `close`. + +There are advantages to each approach. Monkey-patching the fs means +that no `EMFILE` errors can possibly occur anywhere in your +application, because everything is using the same core `fs` module, +which is patched. However, it can also obviously cause undesirable +side-effects, especially if the module is loaded multiple times. + +Implementing a separate-but-identical patched `fs` module is more +surgical (and doesn't run the risk of patching multiple times), but +also imposes the challenge of keeping in sync with the core module. + +The current approach loads the `fs` module, and then creates a +lookalike object that has all the same methods, except a few that are +patched. It is safe to use in all versions of Node from 0.8 through +7.0. + +### v4 + +* Do not monkey-patch the fs module. This module may now be used as a + drop-in dep, and users can opt into monkey-patching the fs builtin + if their app requires it. + +### v3 + +* Monkey-patch fs, because the eval approach no longer works on recent + node. +* fixed possible type-error throw if rename fails on windows +* verify that we *never* get EMFILE errors +* Ignore ENOSYS from chmod/chown +* clarify that graceful-fs must be used as a drop-in + +### v2.1.0 + +* Use eval rather than monkey-patching fs. +* readdir: Always sort the results +* win32: requeue a file if error has an OK status + +### v2.0 + +* A return to monkey patching +* wrap process.cwd + +### v1.1 + +* wrap readFile +* Wrap fs.writeFile. +* readdir protection +* Don't clobber the fs builtin +* Handle fs.read EAGAIN errors by trying again +* Expose the curOpen counter +* No-op lchown/lchmod if not implemented +* fs.rename patch only for win32 +* Patch fs.rename to handle AV software on Windows +* Close #4 Chown should not fail on einval or eperm if non-root +* Fix isaacs/fstream#1 Only wrap fs one time +* Fix #3 Start at 1024 max files, then back off on EMFILE +* lutimes that doens't blow up on Linux +* A full on-rewrite using a queue instead of just swallowing the EMFILE error +* Wrap Read/Write streams as well + +### 1.0 + +* Update engines for node 0.6 +* Be lstat-graceful on Windows +* first |