Re: [hackers] setsid: add optional -f to force fork()

From: Mattias Andrée <maandree_AT_kth.se>
Date: Tue, 14 Jul 2020 12:15:20 +0200

Hi,

Is there any reason you would want to force it?


Regards,
Mattias Andrée


On Tue, 14 Jul 2020 10:15:43 +0200
Hiltjo Posthuma <hiltjo_AT_codemadness.org> wrote:

> Hi,
>
> The below patch adds an -f flag to force fork(2)ing and creating a new process.
>
>
> From a75ef384c11b64732dd6a3adc9249ba6beb8a67e Mon Sep 17 00:00:00 2001
> From: Hiltjo Posthuma <hiltjo_AT_codemadness.org>
> Date: Tue, 14 Jul 2020 10:11:43 +0200
> Subject: [PATCH] setsid: add optional -f to force fork()
>
> ---
> setsid.1 | 3 ++-
> setsid.c | 9 +++++++--
> 2 files changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/setsid.1 b/setsid.1
> index d43bcfc..4df6439 100644
> --- a/setsid.1
> +++ b/setsid.1
> _AT_@ -1,4 +1,4 @@
> -.Dd 2015-10-08
> +.Dd 2020-07-14
> .Dt SETSID 1
> .Os sbase
> .Sh NAME
> _AT_@ -6,6 +6,7 @@
> .Nd run a command in a new session
> .Sh SYNOPSIS
> .Nm
> +.Op Fl f
> .Ar cmd
> .Op Ar arg ...
> .Sh DESCRIPTION
> diff --git a/setsid.c b/setsid.c
> index 28d3442..3355b40 100644
> --- a/setsid.c
> +++ b/setsid.c
> _AT_@ -4,10 +4,12 @@
>
> #include "util.h"
>
> +static int fflag = 0;
> +
> static void
> usage(void)
> {
> - eprintf("usage: %s cmd [arg ...]\n", argv0);
> + eprintf("usage: %s cmd [-f] [arg ...]\n", argv0);
> }
>
> int
> _AT_@ -16,6 +18,9 @@ main(int argc, char *argv[])
> int savederrno;
>
> ARGBEGIN {
> + case 'f':
> + fflag = 1;
> + break;
> default:
> usage();
> } ARGEND
> _AT_@ -23,7 +28,7 @@ main(int argc, char *argv[])
> if (!argc)
> usage();
>
> - if (getpgrp() == getpid()) {
> + if (fflag || getpgrp() == getpid()) {
> switch (fork()) {
> case -1:
> eprintf("fork:");
Received on Tue Jul 14 2020 - 12:15:20 CEST