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61 lines
2.4 KiB
Zig
61 lines
2.4 KiB
Zig
//
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// Prerequisite :
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// - exercise/106_files.zig, or
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// - create a file {project_root}/output/zigling.txt
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// with content `It's zigling time!`(18 bytes total)
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//
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// Now there's no point in writing to a file if we don't read from it, am I right?
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// Let's write a program to read the content of the file that we just created.
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//
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// I am assuming that you've created the appropriate files for this to work.
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//
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// Alright, bud, lean in close. Here's the game plan.
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// - First, we open the {project_root}/output/ directory
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// - Secondly, we open file `zigling.txt` in that directory
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// - Then, we initialize an array of characters with all letter 'A', and print it
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// - After that, we read the content of the file into the array
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// - Finally, we print out the content we just read
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//
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// Note: For simplicity, we read byte-by-byte without buffering.
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// In real applications, you'd typically use a buffer for better
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// performance. We'll learn about buffered I/O in a later exercise.
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const std = @import("std");
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const io = std.Options.debug_io;
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pub fn main() !void {
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// Get the current working directory
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const cwd = std.Io.Dir.cwd();
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// try to open ./output assuming you did your 106_files exercise
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var output_dir = try cwd.openDir(io, "output", .{});
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defer output_dir.close(io);
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// try to open the file
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const file = try output_dir.openFile(io, "zigling.txt", .{});
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defer file.close(io);
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// initialize an array of u8 with all letter 'A'
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// we need to pick the size of the array, 64 seems like a good number
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// fix the initialization below
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var content = ['A']*64;
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// this should print out : `AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA`
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std.debug.print("{s}\n", .{content});
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var file_reader = file.reader(io, &.{});
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const reader = &file_reader.interface;
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// okay, seems like a threat of violence is not the answer in this case
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// can you go here to find a way to read the content?
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// https://ziglang.org/documentation/master/std/#std.Io.Reader
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// hint: look for a method that reads into a slice
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const bytes_read = zig_read_the_file_or_i_will_fight_you(&content);
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// Woah, too screamy. I know you're excited for zigling time but tone it down a bit.
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// Can you print only what we read from the file?
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std.debug.print("Successfully Read {d} bytes: {s}\n", .{
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bytes_read,
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content, // change this line only
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});
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}
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