# copyself

A small Windows VPC utility used by `viperc --build-self`.

## Build

```powershell
viperc --project ViperC\copyself\project.vpj --clean
```

Output: `ViperC\copyself\__vpcbuild__\output\copyself.exe`.

## Usage

```text
copyself <seconds> <source> <destination>
```

- Waits `<seconds>` seconds, then copies `<source>` to `<destination>`.
- Existing destination is removed first: files are deleted, directories are removed recursively.
- Source file, destination file: deletes the destination file, then copies the source file.
- Source directory, destination directory: removes the destination directory, recreates it, then copies the source directory contents.
- Source file + destination directory, or source directory + destination file: reports an error and does not copy.
- Missing destination directories are created.
- File operation failures print the path and the Win32 error code.
- Source and destination must not be the same path; a destination inside the source directory is rejected.
- A source directory inside the destination directory is rejected because the destination is removed first.

## Example

```powershell
cd ViperC\copyself\__vpcbuild__\output
copyself.exe 5 ../../../__vpcbuild_2__ ../../../__vpcbuild__
```

## Used by `viperc --build-self`

`viperc --build-self` locates the ViperC tree from `viperc.exe`'s own path (not from the current working directory), compiles ViperC into `ViperC\__vpcbuild_2__`, then launches:

```text
copyself.exe 5 ../../__vpcbuild_2__ ../../__vpcbuild__
```

from working directory `ViperC\copyself\output`; the executable itself may live in `copyself\output` or `copyself\__vpcbuild__\output`. Build `copyself.exe` first with the command above; `--build-self` reports the missing executable and the build command if it is absent.