readFileAllocOptions
On success, caller owns returned buffer.
If the file is larger than max_bytes, returns error.FileTooBig.
If size_hint is specified the initial buffer size is calculated using
that value, otherwise the effective file size is used instead.
Allows specifying alignment and a sentinel value.
On Windows, file_path should be encoded as WTF-8.
On WASI, file_path should be encoded as valid UTF-8.
On other platforms, file_path is an opaque sequence of bytes with no particular encoding.
Function parameters
Parameters
Type definitions in this namespace
Types
- SymLinkFlags
- Use with `Dir.symLink`, `Dir.atomicSymLink`, and `symLinkAbsolute` to
Functions in this namespace
Functions
- iterateAssumeFirstIteration
- Like `iterate`, but will not reset the directory cursor before the first
- walk
- Recursively iterates over a directory.
- openFile
- Opens a file for reading or writing, without attempting to create a new file.
- openFileZ
- Same as `openFile` but the path parameter is null-terminated.
- openFileW
- Same as `openFile` but Windows-only and the path parameter is
- createFile
- Creates, opens, or overwrites a file with write access.
- createFileZ
- Same as `createFile` but the path parameter is null-terminated.
- createFileW
- Same as `createFile` but Windows-only and the path parameter is
- makeDir
- Creates a single directory with a relative or absolute path.
- makeDirZ
- Same as `makeDir`, but `sub_path` is null-terminated.
- makeDirW
- Creates a single directory with a relative or absolute null-terminated WTF-16 LE-encoded path.
- makePath
- Calls makeDir iteratively to make an entire path
- makePathStatus
- Same as `makePath` except returns whether the path already existed or was successfully created.
- makeOpenPath
- This function performs `makePath`, followed by `openDir`.
- realpath
- This function returns the canonicalized absolute pathname of
- realpathZ
- Same as `Dir.realpath` except `pathname` is null-terminated.
- realpathW
- Windows-only.
- realpathAlloc
- Same as `Dir.realpath` except caller must free the returned memory.
- setAsCwd
- Changes the current working directory to the open directory handle.
- openDir
- Opens a directory at the given path.
- openDirZ
- Same as `openDir` except the parameter is null-terminated.
- openDirW
- Same as `openDir` except the path parameter is WTF-16 LE encoded, NT-prefixed.
- deleteFile
- Delete a file name and possibly the file it refers to, based on an open directory handle.
- deleteFileZ
- Same as `deleteFile` except the parameter is null-terminated.
- deleteFileW
- Same as `deleteFile` except the parameter is WTF-16 LE encoded.
- deleteDir
- Returns `error.DirNotEmpty` if the directory is not empty.
- deleteDirZ
- Same as `deleteDir` except the parameter is null-terminated.
- deleteDirW
- Same as `deleteDir` except the parameter is WTF16LE, NT prefixed.
- rename
- Change the name or location of a file or directory.
- renameZ
- Same as `rename` except the parameters are null-terminated.
- renameW
- Same as `rename` except the parameters are WTF16LE, NT prefixed.
- symLink
- Creates a symbolic link named `sym_link_path` which contains the string `target_path`.
- symLinkWasi
- WASI-only.
- symLinkZ
- Same as `symLink`, except the pathname parameters are null-terminated.
- symLinkW
- Windows-only.
- atomicSymLink
- Same as `symLink`, except tries to create the symbolic link until it
- readLink
- Read value of a symbolic link.
- readLinkWasi
- WASI-only.
- readLinkZ
- Same as `readLink`, except the `sub_path_c` parameter is null-terminated.
- readLinkW
- Windows-only.
- readFile
- Read all of file contents using a preallocated buffer.
- readFileAlloc
- On success, caller owns returned buffer.
- readFileAllocOptions
- On success, caller owns returned buffer.
- deleteTree
- Whether `sub_path` describes a symlink, file, or directory, this function
- deleteTreeMinStackSize
- Like `deleteTree`, but only keeps one `Iterator` active at a time to minimize the function's stack size.
- writeFile
- Writes content to the file system, using the file creation flags provided.
- access
- Test accessing `sub_path`.
- accessZ
- Same as `access` except the path parameter is null-terminated.
- accessW
- Same as `access` except asserts the target OS is Windows and the path parameter is
- updateFile
- Check the file size, mtime, and mode of `source_path` and `dest_path`.
- copyFile
- Atomically creates a new file at `dest_path` within `dest_dir` with the
- atomicFile
- Directly access the `.file` field, and then call `AtomicFile.finish` to
- statFile
- Returns metadata for a file inside the directory.
- chmod
- Changes the mode of the directory.
- chown
- Changes the owner and group of the directory.
- setPermissions
- Sets permissions according to the provided `Permissions` struct.
Error sets in this namespace
Error Sets
= posix.fd_t
Values
- Handle
- = posix.fd_t
- default_mode
- = 0o755
Source
Implementation
pub fn readFileAllocOptions(
self: Dir,
allocator: mem.Allocator,
file_path: []const u8,
max_bytes: usize,
size_hint: ?usize,
comptime alignment: std.mem.Alignment,
comptime optional_sentinel: ?u8,
) !(if (optional_sentinel) |s| [:s]align(alignment.toByteUnits()) u8 else []align(alignment.toByteUnits()) u8) {
var file = try self.openFile(file_path, .{});
defer file.close();
// If the file size doesn't fit a usize it'll be certainly greater than
// `max_bytes`
const stat_size = size_hint orelse std.math.cast(usize, try file.getEndPos()) orelse
return error.FileTooBig;
return file.readToEndAllocOptions(allocator, max_bytes, stat_size, alignment, optional_sentinel);
}