Function getEnvVarOwned [src]

Caller must free returned memory. On Windows, if key is not valid WTF-8, then error.InvalidWtf8 is returned. On Windows, the value is encoded as WTF-8. On other platforms, the value is an opaque sequence of bytes with no particular encoding.

Prototype

pub fn getEnvVarOwned(allocator: Allocator, key: []const u8) GetEnvVarOwnedError![]u8

Parameters

allocator: Allocatorkey: []const u8

Possible Errors

EnvironmentVariableNotFound

InvalidWtf8

On Windows, environment variable keys provided by the user must be valid WTF-8. https://simonsapin.github.io/wtf-8/

OutOfMemory

Example

 test getEnvVarOwned {
    try testing.expectError(
        error.EnvironmentVariableNotFound,
        getEnvVarOwned(std.testing.allocator, "BADENV"),
    );
}

Source

  pub fn getEnvVarOwned(allocator: Allocator, key: []const u8) GetEnvVarOwnedError![]u8 {
    if (native_os == .windows) {
        const result_w = blk: {
            var stack_alloc = std.heap.stackFallback(256 * @sizeOf(u16), allocator);
            const stack_allocator = stack_alloc.get();
            const key_w = try unicode.wtf8ToWtf16LeAllocZ(stack_allocator, key);
            defer stack_allocator.free(key_w);

            break :blk getenvW(key_w) orelse return error.EnvironmentVariableNotFound;
        };
        // wtf16LeToWtf8Alloc can only fail with OutOfMemory
        return unicode.wtf16LeToWtf8Alloc(allocator, result_w);
    } else if (native_os == .wasi and !builtin.link_libc) {
        var envmap = getEnvMap(allocator) catch return error.OutOfMemory;
        defer envmap.deinit();
        const val = envmap.get(key) orelse return error.EnvironmentVariableNotFound;
        return allocator.dupe(u8, val);
    } else {
        const result = posix.getenv(key) orelse return error.EnvironmentVariableNotFound;
        return allocator.dupe(u8, result);
    }
}  