mirror of
https://codeberg.org/andyscott/ziglings.git
synced 2024-11-08 11:20:46 -05:00
92 lines
3.5 KiB
Zig
92 lines
3.5 KiB
Zig
//
|
|
// Until now, we've only been printing our output in the console,
|
|
// which is good enough for fighting alien and hermit bookkeeping.
|
|
//
|
|
// However, many other task require some interaction with the file system,
|
|
// which is the underlying structure for organizing files on your computer.
|
|
//
|
|
// The File System provide a hierarchical structure for storing files
|
|
// by organizing files into directories, which hold files and other directories,
|
|
// thus creating a tree structure for navigating.
|
|
//
|
|
// Fortunately, zig standard library provide a simple api for interacting
|
|
// with the file system, see the detail documentation here
|
|
//
|
|
// https://ziglang.org/documentation/master/std/#std.fs
|
|
//
|
|
// In this exercise, we'll try to
|
|
// - create a new directory
|
|
// - open a file in the directory
|
|
// - write to the file.
|
|
//
|
|
// import std as always
|
|
const std = @import("std");
|
|
|
|
pub fn main() !void {
|
|
// first we get the current working directory
|
|
const cwd: std.fs.Dir = std.fs.cwd();
|
|
|
|
// then we'll try to make a new directory /output/
|
|
// to put our output files.
|
|
cwd.makeDir("output") catch |e| switch (e) {
|
|
// there are chance you might want to run this
|
|
// program more than once and the path might already
|
|
// been created, so we'll have to handle this error
|
|
// by doing nothing
|
|
//
|
|
// we want to catch error.PathAlreadyExists and do nothing
|
|
??? => {},
|
|
// if is any other unexpected error we just propagate it through
|
|
else => return e,
|
|
};
|
|
|
|
// then we'll try to open our freshly created directory
|
|
// wait a minute
|
|
// opening a directory might fail!
|
|
// what should we do here?
|
|
var output_dir: std.fs.Dir = cwd.openDir("output", .{});
|
|
defer output_dir.close();
|
|
|
|
// we try to open the file `zigling.txt`,
|
|
// and propagate the error up if there are any errors
|
|
const file: std.fs.File = try output_dir.createFile("zigling.txt", .{});
|
|
// it is a good habit to close a file after you are done with it
|
|
// so that other programs can read it and prevent data corruption
|
|
// but here we are not yet done writing to the file
|
|
// if only there were a keyword in zig that
|
|
// allows you "defer" code execute to the end of scope...
|
|
file.close();
|
|
|
|
// !you are not allowed to switch these two lines above the file closing line!
|
|
const byte_written = try file.write("It's zigling time!");
|
|
std.debug.print("Successfully wrote {d} bytes.\n", .{byte_written});
|
|
}
|
|
// to check if you actually write to the file, you can either,
|
|
// 1. open the file on your text editor, or
|
|
// 2. print the content of the file in the console with the following command
|
|
// >> cat ./output/zigling.txt
|
|
//
|
|
//
|
|
// More on Creating files
|
|
//
|
|
// notice in:
|
|
// ... try output_dir.createFile("zigling.txt", .{});
|
|
// ^^^
|
|
// we passed this anonymous struct to the function call
|
|
//
|
|
// this is the struct `CreateFlag` with default fields
|
|
// {
|
|
// read: bool = false,
|
|
// truncate: bool = true,
|
|
// exclusive: bool = false,
|
|
// lock: Lock = .none,
|
|
// lock_nonblocking: bool = false,
|
|
// mode: Mode = default_mode
|
|
// }
|
|
//
|
|
// Question:
|
|
// - what should you do if you want to also read the file after opening it?
|
|
// - go to documentation of the struct `std.fs.Dir` here
|
|
// https://ziglang.org/documentation/master/std/#std.fs.Dir
|
|
// - can you find a function for opening a file? how about deleting a file?
|
|
// - what kind of options can you use with those functions?
|