step 1 - read stdin and write to stdout

This commit is contained in:
Paul Campbell 2021-12-29 17:17:13 +00:00
parent 0eb95486a8
commit 2f5da29803

View file

@ -1,7 +1,41 @@
const std = @import("std");
const builtin = @import("builtin");
const File = std.fs.File;
// step 1: [x] read in a file from stdin and write out to stdout
// step 2: [ ] read in a named file in parameters and write out to stdout
// step 3: [ ] skip a number of lines
// step 4: [ ] skip a number of matching lines
// step 5: [ ] skip a number of tokens
pub fn main() anyerror!void {
std.log.info("All your codebase are belong to us.", .{});
const stdin = std.io.getStdIn();
const stdout = std.io.getStdOut();
try dumpInput(stdin, stdout);
}
fn dumpInput(in: File, out: File) !void {
var buffer: [100]u8 = undefined;
while (true) {
const input = (try nextLine(in.reader(), &buffer));
if (input) |line| {
try out.writer().print("{s}\n", .{ line });
} else {
break;
}
}
}
fn nextLine(reader: anytype, buffer: []u8) !?[]const u8 {
var line = (try reader.readUntilDelimiterOrEof(
buffer,
'\n',
)) orelse return null;
// trim annoying windows-only carriage return character
if (builtin.os.tag == .windows) {
line = std.mem.trimRight(u8, line, "\r");
}
return line;
}
test "basic test" {