Re: [PATCH] tsearch.3: Simplify type usage and remove unneeded casts

Michael Kerrisk (man-pages)
2020-09-05T15:35:39Z

Hi Alex,

On 9/5/20 12:50 PM, Alejandro Colomar wrote:
> The type of `var` is `int **`, and it will work with tsearch()
> anyway because of implicit cast from `void *`, so declaring it as an
> `int **` simplifies the code.
>
> Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
> ---
> man3/tsearch.3 | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)

By chance, I've just made a conflicting change, but also...

> diff --git a/man3/tsearch.3 b/man3/tsearch.3
> index 32ddb8127..65fcadc52 100644
> --- a/man3/tsearch.3
> +++ b/man3/tsearch.3
> @@ -323,8 +323,7 @@ action(const void *nodep, VISIT which, int depth)
> int
> main(void)
> {
> - int i, *ptr;
> - void *val;
> + int i, *ptr, **val;

Not quite your fault, since you followed an already poor example,
but many people (and I am one of them) frown on declarations lines
such as the above: 'int', 'int *' and 'int **' are three different
types, and it's considered bad form to declare variables with
different type in one source line. (It's very easy to overlook
an asterisk or two when scanning the source.) Better is:

int i
int *ptr;
int **val;

>
> srand(time(NULL));
> for (i = 0; i < 12; i++) {
> @@ -333,7 +332,7 @@ main(void)
> val = tsearch((void *) ptr, &root, compare);
> if (val == NULL)
> exit(EXIT_FAILURE);
> - else if ((*(int **) val) != ptr)
> + else if (*val != ptr)
> free(ptr);
> }
> twalk(root, action);

Could you please recraft this patch against current Git, which
changed in the last minutes...

Thanks,

Michael

--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/