How to pass argv to std.process.Child.init?

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1

Here’s a minimal working example of the error I’m facing

$ cat run_rick_roll.zig
const std = @import("std");
const log = std.log;

pub fn main() !void {
    var tsa = std.heap.ThreadSafeAllocator{ .child_allocator = std.heap.c_allocator };
    const a = tsa.allocator();
    log.info("Spawning rick roll child process", .{});
    const child = std.process.Child.init(&[_][]u8{ "/bin/bash", "roll.sh" }, a);
    const exit_code = try child.spawnAndWait();

    log.info("Rick rolled with exit code {:}", .{exit_code});
}

This doesn’t compile as expected due to this line

const child = std.process.Child.init(&[_][]u8{ "/bin/bash", "roll.sh" }, a);

Here’s the error

$ zig build-exe -lc run_rick_roll.zig
run_rick_roll.zig:8:52: error: expected type '[]u8', found '*const [9:0]u8'
    const child = std.process.Child.init(&[_][]u8{ "/bin/bash", "roll.sh" }, a);
                                                   ^~~~~~~~~~~
run_rick_roll.zig:8:52: note: cast discards const qualifier
referenced by:
    callMain: /home/cocoa/.local/bin/zig-linux-x86_64-0.13.0/lib/std/start.zig:524:32
    callMainWithArgs: /home/cocoa/.local/bin/zig-linux-x86_64-0.13.0/lib/std/start.zig:482:12
    remaining reference traces hidden; use '-freference-trace' to see all reference traces

Can anybody help me understand how to pass the argument vector?

2

string literals are const as they are located in read only memory, ie change the type to &[_][]const u8{...}
fyi you can replace types with . when initialising to get zig to infer the type ie &.{...}

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