more crimes

src/main.zig

@@ -18,19 +18,13 @@ pub fn main() !void {
         std.process.exit(1);
     }
 
-    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
-    defer _ = gpa.deinit();
-    const allocator = gpa.allocator();
-
-    const args = try std.process.argsAlloc(allocator);
-    defer std.process.argsFree(allocator, args);
-
     var target: u8 = 15;
     var battery: []const u8 = "BAT0";
 
+    var argsIter = std.process.args();
+
     var parse_mode = ParseMode.none;
-    for (args, 0..) |arg, i| {
+    while (argsIter.next()) |arg| {
-        _ = i;
         switch (parse_mode) {
             ParseMode.none => {
                 if (std.mem.eql(u8, arg, "--help")) {
@@ -72,20 +66,23 @@ pub fn main() !void {
     }
 
     var sent = false;
-    const batteryPath = try std.fmt.allocPrint(allocator, "/sys/class/power_supply/{s}/capacity", .{battery});
+    var batBuf: [256]u8 = undefined;
+    var capBuf: [8]u8 = undefined;
+
+    const batteryPath = try std.fmt.bufPrint(&batBuf, "/sys/class/power_supply/{s}/capacity", .{battery});
 
     while (true) {
         const capacityFile = std.fs.openFileAbsolute(batteryPath, .{}) catch |err| {
             std.log.err("open {s}: {}", .{ batteryPath, err });
             std.process.exit(1);
         };
-        var capacityStr = std.ArrayList(u8).init(allocator);
+        _ = try capacityFile.reader().readAll(&capBuf);
-        try capacityFile.reader().streamUntilDelimiter(capacityStr.writer(), '\n', null);
         capacityFile.close();
+        var splat = std.mem.splitScalar(u8, &capBuf, '\n');
 
-        // std.log.info("battery: {s}", .{capacityStr.items});
+        // std.log.info("battery: {s}", .{splat.first()});
 
-        const capacity = try std.fmt.parseInt(u8, capacityStr.items, 10);
+        const capacity = try std.fmt.parseInt(u8, splat.first(), 10);
         // std.log.info("battery (but parsed): {}", .{capacity});
 
         if (capacity <= target) {
@@ -108,7 +105,6 @@ pub fn main() !void {
         } else {
             sent = false;
         }
-        capacityStr.deinit();
 
         std.time.sleep(10 * 1e9);
     }