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SubjectRe: [PATCH] execve.2: execve also returns E2BIG if a string is too long
Hi Rik,

On Tue, Oct 10, 2023 at 11:41:53PM -0400, Rik van Riel wrote:
> Document that if a command line or environment string is too long (> MAX_ARG_STRLEN), execve will also return E2BIG.

That's already implied by the current text:

E2BIG The total number of bytes in the environment (envp) and argument
list (argv) is too large.

That means that

size_t bytes;

bytes = 0;
for (char *e = envp; e != NULL; e++)
bytes += strlen(e) + 1; // I have doubts about the +1
for (char *a = argv; a != NULL; a++)
bytes += strlen(a) + 1; // Same doubts

if (bytes > MAX_ARG_STRLEN) // Maybe >= ?
return -E2BIG;

>
> Signed-off-by: Rik van Riel <riel@surriel.com>
> ---
> man2/execve.2 | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/man2/execve.2 b/man2/execve.2
> index 0d9582492ad1..c1a359d01872 100644
> --- a/man2/execve.2
> +++ b/man2/execve.2
> @@ -449,7 +449,7 @@ The total number of bytes in the environment
> .RI ( envp )
> and argument list
> .RI ( argv )
> -is too large.
> +is too large, or an argument or environment string is too long.

Please use semantic newlines:

$ MANWIDTH=72 man man-pages | sed -n '/Use semantic newlines/,/^$/p'
Use semantic newlines
In the source of a manual page, new sentences should be started
on new lines, long sentences should be split into lines at
clause breaks (commas, semicolons, colons, and so on), and long
clauses should be split at phrase boundaries. This convention,
sometimes known as "semantic newlines", makes it easier to see
the effect of patches, which often operate at the level of in‐
dividual sentences, clauses, or phrases.

Thanks,
Alex

> .TP
> .B EACCES
> Search permission is denied on a component of the path prefix of
> --
> 2.41.0
>
>

--
<https://www.alejandro-colomar.es/>
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