--- title: File --- Utilities for accessing the filesystem & working with files. Many of the functions in this module are not intended to be used directly, but rather for other libraries to be built on top of them. ```grain from "wasi/file" include File ``` ## Types Type declarations included in the File module. ### File.**FileDescriptor** ```grain enum FileDescriptor { FileDescriptor(Number), } ``` Represents a handle to an open file on the system. ### File.**LookupFlag** ```grain enum LookupFlag { SymlinkFollow, } ``` Flags that determine how paths should be resolved when looking up a file or directory. Variants: ```grain SymlinkFollow ``` Follow symlinks ### File.**OpenFlag** ```grain enum OpenFlag { Create, Directory, Exclusive, Truncate, } ``` Flags that determine how a file or directory should be opened. Variants: ```grain Create ``` Create file if it does not exist. ```grain Directory ``` Fail if not a directory. ```grain Exclusive ``` Fail if file already exists. ```grain Truncate ``` Truncate file to size 0. ### File.**Rights** ```grain enum Rights { FdDatasync, FdRead, FdSeek, FdSetFlags, FdSync, FdTell, FdWrite, FdAdvise, FdAllocate, PathCreateDirectory, PathCreateFile, PathLinkSource, PathLinkTarget, PathOpen, FdReaddir, PathReadlink, PathRenameSource, PathRenameTarget, PathFilestats, PathSetSize, PathSetTimes, FdFilestats, FdSetSize, FdSetTimes, PathSymlink, PathRemoveDirectory, PathUnlinkFile, PollFdReadwrite, SockShutdown, } ``` Flags that determine which rights a `FileDescriptor` should have and which rights new `FileDescriptor`s should inherit from it. Variants: ```grain FdDatasync ``` The right to invoke `fdDatasync`. If `PathOpen` is set, includes the right to invoke `pathOpen` with `FdFlag::Dsync`. ```grain FdRead ``` The right to invoke `fdRead`. If `Rights::FdSeek` is set, includes the right to invoke `fdPread`. ```grain FdSeek ``` The right to invoke `fdSeek`. This flag implies `Rights::FdTell`. ```grain FdSetFlags ``` The right to invoke `fdSetFlags`. ```grain FdSync ``` The right to invoke `fdSync`. If `PathOpen` is set, includes the right to invoke `pathOpen` with `FdFlag::Rsync` and `FdFlag::Dsync`. ```grain FdTell ``` The right to invoke `fdSeek` in such a way that the file offset remains unaltered (i.e., `Whence::Current` with offset zero), or to invoke `fdTell`. ```grain FdWrite ``` The right to invoke `fdWrite`. If `Rights::FdSeek` is set, includes the right to invoke `fdPwrite`. ```grain FdAdvise ``` The right to invoke `fdAdvise`. ```grain FdAllocate ``` The right to invoke `fdAllocate`. ```grain PathCreateDirectory ``` The right to invoke `pathCreateDirectory`. ```grain PathCreateFile ``` If `PathOpen` is set, the right to invoke `pathOpen` with `OpenFlag::Create`. ```grain PathLinkSource ``` The right to invoke `pathLink` with the file descriptor as the source directory. ```grain PathLinkTarget ``` The right to invoke `pathLink` with the file descriptor as the target directory. ```grain PathOpen ``` The right to invoke `pathOpen`. ```grain FdReaddir ``` The right to invoke `fdReaddir`. ```grain PathReadlink ``` The right to invoke `pathReadlink`. ```grain PathRenameSource ``` The right to invoke `pathRename` with the file descriptor as the source directory. ```grain PathRenameTarget ``` The right to invoke `pathRename` with the file descriptor as the target directory. ```grain PathFilestats ``` The right to invoke `pathFilestats`. ```grain PathSetSize ``` The right to change a file's size (there's no `pathSetSize`). If `PathOpen` is set, includes the right to invoke `pathOpen` with `OpenFlag::Truncate`. ```grain PathSetTimes ``` The right to invoke `pathSetAccessTime`, `pathSetAccessTimeNow`, `pathSetModifiedTime`, or `pathSetModifiedTimeNow`. ```grain FdFilestats ``` The right to invoke `fdFilestats`. ```grain FdSetSize ``` The right to invoke `fdSetSize`. ```grain FdSetTimes ``` The right to invoke `fdSetAccessTime`, `fdSetAccessTimeNow`, `fdSetModifiedTime`, or `fdSetModifiedTimeNow`. ```grain PathSymlink ``` The right to invoke `pathSymlink`. ```grain PathRemoveDirectory ``` The right to invoke `pathRemoveDirectory`. ```grain PathUnlinkFile ``` The right to invoke `pathUnlinkFile`. ```grain PollFdReadwrite ``` If `Rights::FdRead` is set, includes the right to invoke `pollOneoff` (not yet implemented) to subscribe to `EventType::FdRead`. If `Rights::FdWrite` is set, includes the right to invoke `pollOneoff` (not yet implemented) to subscribe to `EventType::FdWrite`. ```grain SockShutdown ``` The right to invoke `sockShutdown` (not yet implemented). ### File.**FdFlag** ```grain enum FdFlag { Append, Dsync, Nonblock, Rsync, Sync, } ``` Flags that determine the mode(s) that a `FileDescriptor` operates in. Variants: ```grain Append ``` Append mode: Data written to the file is always appended to the file's end. ```grain Dsync ``` Write according to synchronized I/O data integrity completion. Only the data stored in the file is synchronized. ```grain Nonblock ``` Non-blocking mode. ```grain Rsync ``` Synchronized read I/O operations. ### File.**Filetype** ```grain enum Filetype { Unknown, BlockDevice, CharacterDevice, Directory, RegularFile, SocketDatagram, SocketStream, SymbolicLink, } ``` The type of file a `FileDescriptor` refers to. Variants: ```grain Unknown ``` The type of the file descriptor or file is unknown or is different from any of the other types specified. ```grain BlockDevice ``` The file descriptor or file refers to a block device inode. ```grain CharacterDevice ``` The file descriptor or file refers to a character device inode. ```grain Directory ``` The file descriptor or file refers to a directory inode. ```grain RegularFile ``` The file descriptor or file refers to a regular file inode. ```grain SocketDatagram ``` The file descriptor or file refers to a datagram socket. ```grain SocketStream ``` The file descriptor or file refers to a byte-stream socket. ```grain SymbolicLink ``` The file refers to a symbolic link inode. ### File.**Whence** ```grain enum Whence { Set, Current, End, } ``` Flags that determine where seeking should begin in a file. Variants: ```grain Set ``` Seek relative to start-of-file. ```grain Current ``` Seek relative to current position. ```grain End ``` Seek relative to end-of-file. ### File.**Stats** ```grain record Stats { filetype: Filetype, flags: List, rights: List, rightsInheriting: List, } ``` Information about a `FileDescriptor`. ### File.**Filestats** ```grain record Filestats { device: Int64, inode: Int64, filetype: Filetype, linkcount: Int64, size: Int64, accessed: Int64, modified: Int64, changed: Int64, } ``` Information about the file that a `FileDescriptor` refers to. ### File.**DirectoryEntry** ```grain record DirectoryEntry { inode: Int64, filetype: Filetype, path: String, } ``` An entry in a directory. ### File.**Prestat** ```grain enum Prestat { Dir{ prefix: String, fd: FileDescriptor, }, } ``` Information about a preopened directory ## Values Functions and constants included in the File module. ### File.**stdin** ```grain stdin: FileDescriptor ``` The `FileDescriptor` for `stdin`. ### File.**stdout** ```grain stdout: FileDescriptor ``` The `FileDescriptor` for `stdout`. ### File.**stderr** ```grain stderr: FileDescriptor ``` The `FileDescriptor` for `stderr`. ### File.**pathOpen** ```grain pathOpen: (dirFd: FileDescriptor, dirFlags: List, path: String, openFlags: List, rights: List, rightsInheriting: List, flags: List) => Result ``` Open a file or directory. Parameters: | param | type | description | | ------------------ | ------------------ | ------------------------------------------------------------------------------------------------ | | `dirFd` | `FileDescriptor` | The directory in which path resolution starts | | `dirFlags` | `List` | Flags which affect path resolution | | `path` | `String` | The path to the file or directory | | `openFlags` | `List` | Flags that decide how the path will be opened | | `rights` | `List` | The rights that dictate what may be done with the returned file descriptor | | `rightsInheriting` | `List` | The rights that dictate what may be done with file descriptors derived from this file descriptor | | `flags` | `List` | Flags which affect read/write operations on this file descriptor | Returns: | type | description | | ----------------------------------- | ------------------------------------------------------------------------------------ | | `Result` | `Ok(fd)` of the opened file or directory if successful or `Err(exception)` otherwise | ### File.**fdRead** ```grain fdRead: (fd: FileDescriptor, size: Number) => Result<(Bytes, Number), Exception> ``` Read from a file descriptor. Parameters: | param | type | description | | ------ | ---------------- | ------------------------------------------------------------ | | `fd` | `FileDescriptor` | The file descriptor to read from | | `size` | `Number` | The maximum number of bytes to read from the file descriptor | Returns: | type | description | | ------------------------------------ | ----------------------------------------------------------------------------------------------------------------- | | `Result<(Bytes, Number), Exception>` | `Ok((contents, numBytes))` of bytes read and the number of bytes read if successful or `Err(exception)` otherwise | ### File.**fdPread** ```grain fdPread: (fd: FileDescriptor, offset: Int64, size: Number) => Result<(Bytes, Number), Exception> ``` Read from a file descriptor without updating the file descriptor's offset. Parameters: | param | type | description | | -------- | ---------------- | ------------------------------------------------------------ | | `fd` | `FileDescriptor` | The file descriptor to read from | | `offset` | `Int64` | The position within the file to begin reading | | `size` | `Number` | The maximum number of bytes to read from the file descriptor | Returns: | type | description | | ------------------------------------ | ----------------------------------------------------------------------------------------------------------------- | | `Result<(Bytes, Number), Exception>` | `Ok((contents, numBytes))` of bytes read and the number of bytes read if successful or `Err(exception)` otherwise | ### File.**fdPrestatGet**
Added in 0.6.0 No other changes yet.
```grain fdPrestatGet: (fd: FileDescriptor) => Result ``` Get information about a preopened directory. Parameters: | param | type | description | | ----- | ---------------- | ---------------------------- | | `fd` | `FileDescriptor` | The file descriptor to check | Returns: | type | description | | ---------------------------- | ----------------------------------------------------------------- | | `Result` | `Ok(Dir{prefix, fd})` if successful or `Err(exception)` otherwise | ### File.**fdWrite** ```grain fdWrite: (fd: FileDescriptor, data: Bytes) => Result ``` Write to a file descriptor. Parameters: | param | type | description | | ------ | ---------------- | ------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor to which data will be written | | `data` | `Bytes` | The data to be written | Returns: | type | description | | --------------------------- | ----------------------------------------------------------------------------------------- | | `Result` | `Ok(numBytes)` of the number of bytes written if successful or `Err(Exception)` otherwise | ### File.**fdPwrite** ```grain fdPwrite: (fd: FileDescriptor, data: Bytes, offset: Int64) => Result ``` Write to a file descriptor without updating the file descriptor's offset. Parameters: | param | type | description | | -------- | ---------------- | ------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor to which data will be written | | `data` | `Bytes` | The data to be written | | `offset` | `Int64` | The position within the file to begin writing | Returns: | type | description | | --------------------------- | ----------------------------------------------------------------------------------------- | | `Result` | `Ok(numBytes)` of the number of bytes written if successful or `Err(exception)` otherwise | ### File.**fdAllocate** ```grain fdAllocate: (fd: FileDescriptor, offset: Int64, size: Int64) => Result ``` Allocate space within a file. Parameters: | param | type | description | | -------- | ---------------- | ---------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor in which space will be allocated | | `offset` | `Int64` | The position within the file to begin writing | | `size` | `Int64` | The number of bytes to allocate | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdClose** ```grain fdClose: (fd: FileDescriptor) => Result ``` Close a file descriptor. Parameters: | param | type | description | | ----- | ---------------- | ---------------------------- | | `fd` | `FileDescriptor` | The file descriptor to close | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdDatasync** ```grain fdDatasync: (fd: FileDescriptor) => Result ``` Synchronize the data of a file to disk. Parameters: | param | type | description | | ----- | ---------------- | ---------------------------------- | | `fd` | `FileDescriptor` | The file descriptor to synchronize | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdSync** ```grain fdSync: (fd: FileDescriptor) => Result ``` Synchronize the data and metadata of a file to disk. Parameters: | param | type | description | | ----- | ---------------- | ---------------------------------- | | `fd` | `FileDescriptor` | The file descriptor to synchronize | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdStats** ```grain fdStats: (fd: FileDescriptor) => Result ``` Retrieve information about a file descriptor. Parameters: | param | type | description | | ----- | ---------------- | ---------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of which to retrieve information | Returns: | type | description | | -------------------------- | ---------------------------------------------------------------------------------------------------------- | | `Result` | `Ok(stats)` of the `Stats` associated with the file descriptor if successful or `Err(exception)` otherwise | ### File.**fdSetFlags** ```grain fdSetFlags: (fd: FileDescriptor, flags: List) => Result ``` Update the flags associated with a file descriptor. Parameters: | param | type | description | | ------- | ---------------- | ----------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor to update flags | | `flags` | `List` | The flags to apply to the file descriptor | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdSetRights** ```grain fdSetRights: (fd: FileDescriptor, rights: List, rightsInheriting: List) => Result ``` Update the rights associated with a file descriptor. Parameters: | param | type | description | | ------------------ | ---------------- | ------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor to update rights | | `rights` | `List` | Rights to apply to the file descriptor | | `rightsInheriting` | `List` | Inheriting rights to apply to the file descriptor | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdFilestats** ```grain fdFilestats: (fd: FileDescriptor) => Result ``` Retrieve information about a file. Parameters: | param | type | description | | ----- | ---------------- | ------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the file to retrieve information | Returns: | type | description | | ------------------------------ | ------------------------------------------------------------------------------------------------------------- | | `Result` | `Ok(info)` of the `Filestats` associated with the file descriptor if successful or `Err(exception)` otherwise | ### File.**fdSetSize** ```grain fdSetSize: (fd: FileDescriptor, size: Int64) => Result ``` Set (truncate) the size of a file. Parameters: | param | type | description | | ------ | ---------------- | ------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the file to truncate | | `size` | `Int64` | The number of bytes to retain in the file | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdSetAccessTime** ```grain fdSetAccessTime: (fd: FileDescriptor, timestamp: Int64) => Result ``` Set the access (created) time of a file. Parameters: | param | type | description | | ----------- | ---------------- | ----------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the file to update | | `timestamp` | `Int64` | The time to set | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdSetAccessTimeNow** ```grain fdSetAccessTimeNow: (fd: FileDescriptor) => Result ``` Set the access (created) time of a file to the current time. Parameters: | param | type | description | | ----- | ---------------- | ----------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the file to update | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdSetModifiedTime** ```grain fdSetModifiedTime: (fd: FileDescriptor, timestamp: Int64) => Result ``` Set the modified time of a file. Parameters: | param | type | description | | ----------- | ---------------- | ----------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the file to update | | `timestamp` | `Int64` | The time to set | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdSetModifiedTimeNow** ```grain fdSetModifiedTimeNow: (fd: FileDescriptor) => Result ``` Set the modified time of a file to the current time. Parameters: | param | type | description | | ----- | ---------------- | ----------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the file to update | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdReaddir** ```grain fdReaddir: (fd: FileDescriptor) => Result, Exception> ``` Read the entires of a directory. Parameters: | param | type | description | | ----- | ---------------- | --------------------- | | `fd` | `FileDescriptor` | The directory to read | Returns: | type | description | | ------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------- | | `Result, Exception>` | `Ok(dirEntries)` of an array of `DirectoryEntry` for each entry in the directory if successful or `Err(exception)` otherwise | ### File.**fdRenumber** ```grain fdRenumber: (fromFd: FileDescriptor, toFd: FileDescriptor) => Result ``` Atomically replace a file descriptor by renumbering another file descriptor. Parameters: | param | type | description | | -------- | ---------------- | -------------------------------- | | `fromFd` | `FileDescriptor` | The file descriptor to renumber | | `toFd` | `FileDescriptor` | The file descriptor to overwrite | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**fdSeek** ```grain fdSeek: (fd: FileDescriptor, offset: Int64, whence: Whence) => Result ``` Update a file descriptor's offset. Parameters: | param | type | description | | -------- | ---------------- | ---------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor to operate on | | `offset` | `Int64` | The number of bytes to move the offset | | `whence` | `Whence` | The location from which the offset is relative | Returns: | type | description | | -------------------------- | ------------------------------------------------------------------------------------------------------------------------------------- | | `Result` | `Ok(offset)` of the new offset of the file descriptor, relative to the start of the file, if successful or `Err(exception)` otherwise | ### File.**fdTell** ```grain fdTell: (fd: FileDescriptor) => Result ``` Read a file descriptor's offset. Parameters: | param | type | description | | ----- | ---------------- | -------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor to read the offset | Returns: | type | description | | -------------------------- | --------------------------------------------------------------------------------------------------------------------------------- | | `Result` | `Ok(offset)` of the offset of the file descriptor, relative to the start of the file, if successful or `Err(exception)` otherwise | ### File.**pathCreateDirectory** ```grain pathCreateDirectory: (fd: FileDescriptor, path: String) => Result ``` Create a directory. Parameters: | param | type | description | | ------ | ---------------- | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `path` | `String` | The path to the new directory | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**pathFilestats** ```grain pathFilestats: (fd: FileDescriptor, dirFlags: List, path: String) => Result ``` Retrieve information about a file. Parameters: | param | type | description | | ---------- | ------------------ | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `dirFlags` | `List` | Flags which affect path resolution | | `path` | `String` | The path to retrieve information about | Returns: | type | description | | ------------------------------ | ------------------------------------------------------------------------------------------------------------- | | `Result` | `Ok(info)` of the `Filestats` associated with the file descriptor if successful or `Err(exception)` otherwise | ### File.**pathSetAccessTime** ```grain pathSetAccessTime: (fd: FileDescriptor, dirFlags: List, path: String, timestamp: Int64) => Result ``` Set the access (created) time of a file. Parameters: | param | type | description | | ----------- | ------------------ | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `dirFlags` | `List` | Flags which affect path resolution | | `path` | `String` | The path to set the time | | `timestamp` | `Int64` | The time to set | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**pathSetAccessTimeNow** ```grain pathSetAccessTimeNow: (fd: FileDescriptor, dirFlags: List, path: String) => Result ``` Set the access (created) time of a file to the current time. Parameters: | param | type | description | | ---------- | ------------------ | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `dirFlags` | `List` | Flags which affect path resolution | | `path` | `String` | The path to set the time | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**pathSetModifiedTime** ```grain pathSetModifiedTime: (fd: FileDescriptor, dirFlags: List, path: String, timestamp: Int64) => Result ``` Set the modified time of a file. Parameters: | param | type | description | | ----------- | ------------------ | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `dirFlags` | `List` | Flags which affect path resolution | | `path` | `String` | The path to set the time | | `timestamp` | `Int64` | The time to set | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**pathSetModifiedTimeNow** ```grain pathSetModifiedTimeNow: (fd: FileDescriptor, dirFlags: List, path: String) => Result ``` Set the modified time of a file to the current time. Parameters: | param | type | description | | ---------- | ------------------ | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `dirFlags` | `List` | Flags which affect path resolution | | `path` | `String` | The path to set the time | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**pathLink** ```grain pathLink: (sourceFd: FileDescriptor, dirFlags: List, sourcePath: String, targetFd: FileDescriptor, targetPath: String) => Result ``` Create a hard link. Parameters: | param | type | description | | ------------ | ------------------ | ------------------------------------------------------------------------------- | | `sourceFd` | `FileDescriptor` | The file descriptor of the directory in which the source path resolution starts | | `dirFlags` | `List` | Flags which affect path resolution | | `sourcePath` | `String` | The path to the source of the link | | `targetFd` | `FileDescriptor` | The file descriptor of the directory in which the target path resolution starts | | `targetPath` | `String` | The path to the target of the link | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**pathSymlink** ```grain pathSymlink: (fd: FileDescriptor, sourcePath: String, targetPath: String) => Result ``` Create a symlink. Parameters: | param | type | description | | ------------ | ---------------- | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `sourcePath` | `String` | The path to the source of the link | | `targetPath` | `String` | The path to the target of the link | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**pathUnlink** ```grain pathUnlink: (fd: FileDescriptor, path: String) => Result ``` Unlink a file. Parameters: | param | type | description | | ------ | ---------------- | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `path` | `String` | The path of the file to unlink | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**pathReadlink** ```grain pathReadlink: (fd: FileDescriptor, path: String, size: Number) => Result<(String, Number), Exception> ``` Read the contents of a symbolic link. Parameters: | param | type | description | | ------ | ---------------- | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `path` | `String` | The path to the symlink | | `size` | `Number` | The number of bytes to read | Returns: | type | description | | ------------------------------------- | --------------------------------------------------------------------------------------------------------------------- | | `Result<(String, Number), Exception>` | `Ok((contents, numBytes))` of the bytes read and the number of bytes read if successful or `Err(exception)` otherwise | ### File.**pathRemoveDirectory** ```grain pathRemoveDirectory: (fd: FileDescriptor, path: String) => Result ``` Remove a directory. Parameters: | param | type | description | | ------ | ---------------- | -------------------------------------------------------------------- | | `fd` | `FileDescriptor` | The file descriptor of the directory in which path resolution starts | | `path` | `String` | The path to the directory to remove | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**pathRename** ```grain pathRename: (sourceFd: FileDescriptor, sourcePath: String, targetFd: FileDescriptor, targetPath: String) => Result ``` Rename a file or directory. Parameters: | param | type | description | | ------------ | ---------------- | ------------------------------------------------------------------------------- | | `sourceFd` | `FileDescriptor` | The file descriptor of the directory in which the source path resolution starts | | `sourcePath` | `String` | The path of the file to rename | | `targetFd` | `FileDescriptor` | The file descriptor of the directory in which the target path resolution starts | | `targetPath` | `String` | The new path of the file | Returns: | type | description | | ------------------------- | ------------------------------------------------------ | | `Result` | `Ok(void)` if successful or `Err(exception)` otherwise | ### File.**open**
Added in 0.6.0 No other changes yet.
```grain open: (path: String, openFlags: List, rights: List, rightsInheriting: List, flags: List) => Result ``` Similar to `pathOpen`, but resolves the path relative to preopened directories. Parameters: | param | type | description | | ------------------ | ---------------- | ------------------------------------------------------------------------------------------------ | | `path` | `String` | The path to the file or directory | | `openFlags` | `List` | Flags that decide how the path will be opened | | `rights` | `List` | The rights that dictate what may be done with the returned file descriptor | | `rightsInheriting` | `List` | The rights that dictate what may be done with file descriptors derived from this file descriptor | | `flags` | `List` | Flags which affect read/write operations on this file descriptor | Returns: | type | description | | ----------------------------------- | ------------------------------------------------------------------------------------ | | `Result` | `Ok(fd)` of the opened file or directory if successful or `Err(exception)` otherwise |