Re: [PATCH] restart_syscall.2: SYNOPSIS: Fix restart_syscall() return type

[Michael Kerrisk (man-pages)]

Hi Alex,

On 11/23/20 9:34 PM, Alejandro Colomar wrote:
> The Linux kernel uses 'long' instead of 'int' for the return type.
> As glibc provides no wrapper, use the same types the kernel uses.
> 
> $ grep -rn 'SYSCALL_DEFINE.*(restart_syscall'
> kernel/signal.c:2891:SYSCALL_DEFINE0(restart_syscall)
> 
> $ sed -n 2891,2895p kernel/signal.c
> SYSCALL_DEFINE0(restart_syscall)
> {
>       struct restart_block *restart = &current->restart_block;
>       return restart->fn(restart);
> }
> 
> $ grep -rn 'struct restart_block {'
> include/linux/restart_block.h:25:struct restart_block {
> 
> $ sed -n 25,56p include/linux/restart_block.h
> struct restart_block {
>       long (*fn)(struct restart_block *);
>       union {
>               /* For futex_wait and futex_wait_requeue_pi */
>               struct {
>                       u32 __user *uaddr;
>                       u32 val;
>                       u32 flags;
>                       u32 bitset;
>                       u64 time;
>                       u32 __user *uaddr2;
>               } futex;
>               /* For nanosleep */
>               struct {
>                       clockid_t clockid;
>                       enum timespec_type type;
>                       union {
>                               struct __kernel_timespec __user *rmtp;
>                               struct old_timespec32 __user *compat_rmtp;
>                       };
>                       u64 expires;
>               } nanosleep;
>               /* For poll */
>               struct {
>                       struct pollfd __user *ufds;
>                       int nfds;
>                       int has_timeout;
>                       unsigned long tv_sec;
>                       unsigned long tv_nsec;
>               } poll;
>       };
> };
> 
> Signed-off-by: Alejandro Colomar <alx.manpa...@gmail.com>

Thanks! Patch applied.

Cheers,

Michael

> ---
>  man2/restart_syscall.2 | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/man2/restart_syscall.2 b/man2/restart_syscall.2
> index e7d96bd4d..21cc2df1d 100644
> --- a/man2/restart_syscall.2
> +++ b/man2/restart_syscall.2
> @@ -34,7 +34,7 @@
>  .SH NAME
>  restart_syscall \- restart a system call after interruption by a stop signal
>  .SH SYNOPSIS
> -.B int restart_syscall(void);
> +.B long restart_syscall(void);
>  .PP
>  .IR Note :
>  There is no glibc wrapper for this system call; see NOTES.
> 


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