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* [PATCH] ptrace.2: document PTRACE_GET_SYSCALL_INFO
@ 2019-09-02 12:38 Dmitry V. Levin
  2019-09-10 10:51 ` Michael Kerrisk (man-pages)
  0 siblings, 1 reply; 7+ messages in thread
From: Dmitry V. Levin @ 2019-09-02 12:38 UTC (permalink / raw)
  To: Michael Kerrisk; +Cc: Elvira Khabirova, linux-man

PTRACE_GET_SYSCALL_INFO request was introduced by Linux kernel commit
201766a20e30f982ccfe36bebfad9602c3ff574a aka v5.3-rc1~65^2~23.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
---
 man2/ptrace.2 | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/man2/ptrace.2 b/man2/ptrace.2
index 8b8daf238..3b774f87b 100644
--- a/man2/ptrace.2
+++ b/man2/ptrace.2
@@ -1005,6 +1005,27 @@ of the
 .IR "struct user_desc"
 is ignored; in other words,
 this ptrace operation can't be used to allocate a free TLS entry.)
+.TP
+.BR PTRACE_GET_SYSCALL_INFO " (since Linux 5.3)"
+.\" commit 201766a20e30f982ccfe36bebfad9602c3ff574a
+Retrieve information about the syscall that caused the stop.
+The information is placed into the buffer pointed by
+.I data
+argument, which should be a pointer to a buffer of type
+.IR "struct ptrace_syscall_info" .
+The
+.I addr
+argument contains the size of the buffer pointed to
+by
+.I data
+argument (i.e.,
+.IR "sizeof(struct ptrace_syscall_info)" ).
+The return value contains the number of bytes available
+to be written by the kernel.
+If the size of data to be written by the kernel exceeds the size
+specified by
+.I addr
+argument, the output is truncated.
 .\"
 .SS Death under ptrace
 When a (possibly multithreaded) process receives a killing signal

-- 
ldv

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH] ptrace.2: document PTRACE_GET_SYSCALL_INFO
  2019-09-02 12:38 [PATCH] ptrace.2: document PTRACE_GET_SYSCALL_INFO Dmitry V. Levin
@ 2019-09-10 10:51 ` Michael Kerrisk (man-pages)
  2019-09-11 17:38   ` [PATCH] ptrace.2: document struct ptrace_syscall_info Dmitry V. Levin
  0 siblings, 1 reply; 7+ messages in thread
From: Michael Kerrisk (man-pages) @ 2019-09-10 10:51 UTC (permalink / raw)
  To: Dmitry V. Levin; +Cc: mtk.manpages, Elvira Khabirova, linux-man

Hello Dmitry,

On 9/2/19 2:38 PM, Dmitry V. Levin wrote:
> PTRACE_GET_SYSCALL_INFO request was introduced by Linux kernel commit
> 201766a20e30f982ccfe36bebfad9602c3ff574a aka v5.3-rc1~65^2~23.
> 
> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
> ---
>  man2/ptrace.2 | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/man2/ptrace.2 b/man2/ptrace.2
> index 8b8daf238..3b774f87b 100644
> --- a/man2/ptrace.2
> +++ b/man2/ptrace.2
> @@ -1005,6 +1005,27 @@ of the
>  .IR "struct user_desc"
>  is ignored; in other words,
>  this ptrace operation can't be used to allocate a free TLS entry.)
> +.TP
> +.BR PTRACE_GET_SYSCALL_INFO " (since Linux 5.3)"
> +.\" commit 201766a20e30f982ccfe36bebfad9602c3ff574a
> +Retrieve information about the syscall that caused the stop.
> +The information is placed into the buffer pointed by
> +.I data
> +argument, which should be a pointer to a buffer of type
> +.IR "struct ptrace_syscall_info" .
> +The
> +.I addr
> +argument contains the size of the buffer pointed to
> +by
> +.I data
> +argument (i.e.,
> +.IR "sizeof(struct ptrace_syscall_info)" ).
> +The return value contains the number of bytes available
> +to be written by the kernel.
> +If the size of data to be written by the kernel exceeds the size
> +specified by
> +.I addr
> +argument, the output is truncated.
>  .\"
>  .SS Death under ptrace
>  When a (possibly multithreaded) process receives a killing signal

Thanks for this patch. I've applied, tweaked the wording very
slightly, and pushed.

However, this patch lacks an important piece: documentation of
'struct ptrace_syscall_info'. I could take a shot at this, but 
I see you already wrote a test program for this ptrace operation. 
Would you be willing to add a patch that documents the structure?

Thanks,

Michael

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

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH] ptrace.2: document struct ptrace_syscall_info
  2019-09-10 10:51 ` Michael Kerrisk (man-pages)
@ 2019-09-11 17:38   ` Dmitry V. Levin
  2019-09-12  9:17     ` Michael Kerrisk (man-pages)
  0 siblings, 1 reply; 7+ messages in thread
From: Dmitry V. Levin @ 2019-09-11 17:38 UTC (permalink / raw)
  To: Michael Kerrisk (man-pages); +Cc: Elvira Khabirova, linux-man

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
---
 man2/ptrace.2 | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 50 insertions(+), 1 deletion(-)

diff --git a/man2/ptrace.2 b/man2/ptrace.2
index ff897bb19..b030247e6 100644
--- a/man2/ptrace.2
+++ b/man2/ptrace.2
@@ -1026,7 +1026,56 @@ If the size of the data to be written by the kernel exceeds the size
 specified by the
 .I addr
 argument, the output data is truncated.
-.\" FIXME Document 'struct ptrace_syscall_info'
+.IP
+The
+.I ptrace_syscall_info
+structure contains the following fields:
+.IP
+.in
+.EX
+struct ptrace_syscall_info {
+    __u8 op;                    /* PTRACE_SYSCALL_INFO_* value
+                                   describing the kind
+                                   of system call stop,
+                                   see <linux/ptrace.h> */
+    __u32 arch;                 /* AUDIT_ARCH_* value,
+                                   see seccomp(2) */
+    __u64 instruction_pointer;  /* CPU instruction pointer */
+    __u64 stack_pointer;        /* CPU stack pointer */
+    union {
+        struct {
+            __u64 nr;           /* System call number */
+            __u64 args[6];      /* System call arguments */
+        } entry;                /* Information specific to
+                                   system call entry stops */
+        struct {
+            __s64 rval;         /* System call return value */
+            __u8 is_error;      /* System call error flag */
+        } exit;                 /* Information specific to
+                                   system call exit stops */
+        struct {
+            __u64 nr;           /* System call number */
+            __u64 args[6];      /* System call arguments */
+            __u32 ret_data;     /* The SECCOMP_RET_DATA portion
+                                   of SECCOMP_RET_TRACE return
+                                   value */
+        } seccomp;              /* Information specific to
+                                   PTRACE_EVENT_SECCOMP stops */
+    };
+};
+.EE
+.in
+.IP
+.IR op ,
+.IR arch ,
+.IR instruction_pointer ,
+and
+.I stack_pointer
+fields are defined for all kinds of ptrace system call stops.
+The rest of the structure is a union, one should read only those fields
+that are meaningful for the kind of system call stop specified by the
+.IR op
+field.
 .\"
 .SS Death under ptrace
 When a (possibly multithreaded) process receives a killing signal
-- 
ldv

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH] ptrace.2: document struct ptrace_syscall_info
  2019-09-11 17:38   ` [PATCH] ptrace.2: document struct ptrace_syscall_info Dmitry V. Levin
@ 2019-09-12  9:17     ` Michael Kerrisk (man-pages)
  2019-09-13 15:40       ` Dmitry V. Levin
  0 siblings, 1 reply; 7+ messages in thread
From: Michael Kerrisk (man-pages) @ 2019-09-12  9:17 UTC (permalink / raw)
  To: Dmitry V. Levin; +Cc: mtk.manpages, Elvira Khabirova, linux-man

Hello Dmitry,

On 9/11/19 7:38 PM, Dmitry V. Levin wrote:
> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
> ---
>  man2/ptrace.2 | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 50 insertions(+), 1 deletion(-)
> 
> diff --git a/man2/ptrace.2 b/man2/ptrace.2
> index ff897bb19..b030247e6 100644
> --- a/man2/ptrace.2
> +++ b/man2/ptrace.2
> @@ -1026,7 +1026,56 @@ If the size of the data to be written by the kernel exceeds the size
>  specified by the
>  .I addr
>  argument, the output data is truncated.
> -.\" FIXME Document 'struct ptrace_syscall_info'
> +.IP
> +The
> +.I ptrace_syscall_info
> +structure contains the following fields:
> +.IP
> +.in
> +.EX
> +struct ptrace_syscall_info {
> +    __u8 op;                    /* PTRACE_SYSCALL_INFO_* value
> +                                   describing the kind
> +                                   of system call stop,
> +                                   see <linux/ptrace.h> */
> +    __u32 arch;                 /* AUDIT_ARCH_* value,
> +                                   see seccomp(2) */
> +    __u64 instruction_pointer;  /* CPU instruction pointer */
> +    __u64 stack_pointer;        /* CPU stack pointer */
> +    union {
> +        struct {
> +            __u64 nr;           /* System call number */
> +            __u64 args[6];      /* System call arguments */
> +        } entry;                /* Information specific to
> +                                   system call entry stops */
> +        struct {
> +            __s64 rval;         /* System call return value */
> +            __u8 is_error;      /* System call error flag */
> +        } exit;                 /* Information specific to
> +                                   system call exit stops */
> +        struct {
> +            __u64 nr;           /* System call number */
> +            __u64 args[6];      /* System call arguments */
> +            __u32 ret_data;     /* The SECCOMP_RET_DATA portion
> +                                   of SECCOMP_RET_TRACE return
> +                                   value */
> +        } seccomp;              /* Information specific to
> +                                   PTRACE_EVENT_SECCOMP stops */
> +    };
> +};
> +.EE
> +.in
> +.IP
> +.IR op ,
> +.IR arch ,
> +.IR instruction_pointer ,
> +and
> +.I stack_pointer
> +fields are defined for all kinds of ptrace system call stops.
> +The rest of the structure is a union, one should read only those fields
> +that are meaningful for the kind of system call stop specified by the
> +.IR op
> +field.
>  .\"
>  .SS Death under ptrace
>  When a (possibly multithreaded) process receives a killing signal

Thanks. I've applied, and done some light editing.

I also added some pieces. Could you please take a look at commits
f04534d22c69 [1] and 227a3682312 [2] let me know if they are okay.


Thanks,

Michael

[1] https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/commit/?id=f04534d22c69a947c3cfee82b9a683e772e913b4
[2] https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/commit/?id=227a3682312212c8848e9e972a1f923c6a8ad531

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

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH] ptrace.2: document struct ptrace_syscall_info
  2019-09-12  9:17     ` Michael Kerrisk (man-pages)
@ 2019-09-13 15:40       ` Dmitry V. Levin
  2019-09-13 18:48         ` Michael Kerrisk (man-pages)
  0 siblings, 1 reply; 7+ messages in thread
From: Dmitry V. Levin @ 2019-09-13 15:40 UTC (permalink / raw)
  To: Michael Kerrisk (man-pages); +Cc: Elvira Khabirova, linux-man

On Thu, Sep 12, 2019 at 11:17:52AM +0200, Michael Kerrisk (man-pages) wrote:
> Hello Dmitry,
> 
> On 9/11/19 7:38 PM, Dmitry V. Levin wrote:
> > Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
> > ---
> >  man2/ptrace.2 | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 50 insertions(+), 1 deletion(-)
> > 
> > diff --git a/man2/ptrace.2 b/man2/ptrace.2
> > index ff897bb19..b030247e6 100644
> > --- a/man2/ptrace.2
> > +++ b/man2/ptrace.2
> > @@ -1026,7 +1026,56 @@ If the size of the data to be written by the kernel exceeds the size
> >  specified by the
> >  .I addr
> >  argument, the output data is truncated.
> > -.\" FIXME Document 'struct ptrace_syscall_info'
> > +.IP
> > +The
> > +.I ptrace_syscall_info
> > +structure contains the following fields:
> > +.IP
> > +.in
> > +.EX
> > +struct ptrace_syscall_info {
> > +    __u8 op;                    /* PTRACE_SYSCALL_INFO_* value
> > +                                   describing the kind
> > +                                   of system call stop,
> > +                                   see <linux/ptrace.h> */
> > +    __u32 arch;                 /* AUDIT_ARCH_* value,
> > +                                   see seccomp(2) */
> > +    __u64 instruction_pointer;  /* CPU instruction pointer */
> > +    __u64 stack_pointer;        /* CPU stack pointer */
> > +    union {
> > +        struct {
> > +            __u64 nr;           /* System call number */
> > +            __u64 args[6];      /* System call arguments */
> > +        } entry;                /* Information specific to
> > +                                   system call entry stops */
> > +        struct {
> > +            __s64 rval;         /* System call return value */
> > +            __u8 is_error;      /* System call error flag */
> > +        } exit;                 /* Information specific to
> > +                                   system call exit stops */
> > +        struct {
> > +            __u64 nr;           /* System call number */
> > +            __u64 args[6];      /* System call arguments */
> > +            __u32 ret_data;     /* The SECCOMP_RET_DATA portion
> > +                                   of SECCOMP_RET_TRACE return
> > +                                   value */
> > +        } seccomp;              /* Information specific to
> > +                                   PTRACE_EVENT_SECCOMP stops */
> > +    };
> > +};
> > +.EE
> > +.in
> > +.IP
> > +.IR op ,
> > +.IR arch ,
> > +.IR instruction_pointer ,
> > +and
> > +.I stack_pointer
> > +fields are defined for all kinds of ptrace system call stops.
> > +The rest of the structure is a union, one should read only those fields
> > +that are meaningful for the kind of system call stop specified by the
> > +.IR op
> > +field.
> >  .\"
> >  .SS Death under ptrace
> >  When a (possibly multithreaded) process receives a killing signal
> 
> Thanks. I've applied, and done some light editing.
> 
> I also added some pieces. Could you please take a look at commits
> f04534d22c69 [1] and 227a3682312 [2] let me know if they are okay.

Thanks.  The only thing that needs correction is
"Boolean: is rval != 0?" comment about is_error field.

In fact, is_error is a boolean that tells whether rval field
contains a non-error return value (e.g. file descriptor) or
an error value (e.g. -ERRORCODE).


-- 
ldv

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH] ptrace.2: document struct ptrace_syscall_info
  2019-09-13 15:40       ` Dmitry V. Levin
@ 2019-09-13 18:48         ` Michael Kerrisk (man-pages)
  2019-09-13 19:37           ` Dmitry V. Levin
  0 siblings, 1 reply; 7+ messages in thread
From: Michael Kerrisk (man-pages) @ 2019-09-13 18:48 UTC (permalink / raw)
  To: Dmitry V. Levin; +Cc: mtk.manpages, Elvira Khabirova, linux-man

On 9/13/19 5:40 PM, Dmitry V. Levin wrote:
> On Thu, Sep 12, 2019 at 11:17:52AM +0200, Michael Kerrisk (man-pages) wrote:
>> Hello Dmitry,
>>
>> On 9/11/19 7:38 PM, Dmitry V. Levin wrote:
>>> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
>>> ---
>>>  man2/ptrace.2 | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++-
>>>  1 file changed, 50 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/man2/ptrace.2 b/man2/ptrace.2
>>> index ff897bb19..b030247e6 100644
>>> --- a/man2/ptrace.2
>>> +++ b/man2/ptrace.2
>>> @@ -1026,7 +1026,56 @@ If the size of the data to be written by the kernel exceeds the size
>>>  specified by the
>>>  .I addr
>>>  argument, the output data is truncated.
>>> -.\" FIXME Document 'struct ptrace_syscall_info'
>>> +.IP
>>> +The
>>> +.I ptrace_syscall_info
>>> +structure contains the following fields:
>>> +.IP
>>> +.in
>>> +.EX
>>> +struct ptrace_syscall_info {
>>> +    __u8 op;                    /* PTRACE_SYSCALL_INFO_* value
>>> +                                   describing the kind
>>> +                                   of system call stop,
>>> +                                   see <linux/ptrace.h> */
>>> +    __u32 arch;                 /* AUDIT_ARCH_* value,
>>> +                                   see seccomp(2) */
>>> +    __u64 instruction_pointer;  /* CPU instruction pointer */
>>> +    __u64 stack_pointer;        /* CPU stack pointer */
>>> +    union {
>>> +        struct {
>>> +            __u64 nr;           /* System call number */
>>> +            __u64 args[6];      /* System call arguments */
>>> +        } entry;                /* Information specific to
>>> +                                   system call entry stops */
>>> +        struct {
>>> +            __s64 rval;         /* System call return value */
>>> +            __u8 is_error;      /* System call error flag */
>>> +        } exit;                 /* Information specific to
>>> +                                   system call exit stops */
>>> +        struct {
>>> +            __u64 nr;           /* System call number */
>>> +            __u64 args[6];      /* System call arguments */
>>> +            __u32 ret_data;     /* The SECCOMP_RET_DATA portion
>>> +                                   of SECCOMP_RET_TRACE return
>>> +                                   value */
>>> +        } seccomp;              /* Information specific to
>>> +                                   PTRACE_EVENT_SECCOMP stops */
>>> +    };
>>> +};
>>> +.EE
>>> +.in
>>> +.IP
>>> +.IR op ,
>>> +.IR arch ,
>>> +.IR instruction_pointer ,
>>> +and
>>> +.I stack_pointer
>>> +fields are defined for all kinds of ptrace system call stops.
>>> +The rest of the structure is a union, one should read only those fields
>>> +that are meaningful for the kind of system call stop specified by the
>>> +.IR op
>>> +field.
>>>  .\"
>>>  .SS Death under ptrace
>>>  When a (possibly multithreaded) process receives a killing signal
>>
>> Thanks. I've applied, and done some light editing.
>>
>> I also added some pieces. Could you please take a look at commits
>> f04534d22c69 [1] and 227a3682312 [2] let me know if they are okay.
> 
> Thanks.  The only thing that needs correction is
> "Boolean: is rval != 0?" comment about is_error field.
> 
> In fact, is_error is a boolean that tells whether rval field
> contains a non-error return value (e.g. file descriptor) or
> an error value (e.g. -ERRORCODE).

Thanks for checking this Dmitry. I see what I missed before.
I've now changed the text here to be:

            __u8 is_error;     /* System call error flag;
                                  Boolean: does rval contain
                                  an error value (\-ERRCODE) or
                                  a nonerror return value? */

Thanks,

Michael



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

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH] ptrace.2: document struct ptrace_syscall_info
  2019-09-13 18:48         ` Michael Kerrisk (man-pages)
@ 2019-09-13 19:37           ` Dmitry V. Levin
  0 siblings, 0 replies; 7+ messages in thread
From: Dmitry V. Levin @ 2019-09-13 19:37 UTC (permalink / raw)
  To: Michael Kerrisk (man-pages); +Cc: Elvira Khabirova, linux-man

On Fri, Sep 13, 2019 at 08:48:21PM +0200, Michael Kerrisk (man-pages) wrote:
> On 9/13/19 5:40 PM, Dmitry V. Levin wrote:
> > On Thu, Sep 12, 2019 at 11:17:52AM +0200, Michael Kerrisk (man-pages) wrote:
> >> Hello Dmitry,
> >>
> >> On 9/11/19 7:38 PM, Dmitry V. Levin wrote:
> >>> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
> >>> ---
> >>>  man2/ptrace.2 | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++-
> >>>  1 file changed, 50 insertions(+), 1 deletion(-)
> >>>
> >>> diff --git a/man2/ptrace.2 b/man2/ptrace.2
> >>> index ff897bb19..b030247e6 100644
> >>> --- a/man2/ptrace.2
> >>> +++ b/man2/ptrace.2
> >>> @@ -1026,7 +1026,56 @@ If the size of the data to be written by the kernel exceeds the size
> >>>  specified by the
> >>>  .I addr
> >>>  argument, the output data is truncated.
> >>> -.\" FIXME Document 'struct ptrace_syscall_info'
> >>> +.IP
> >>> +The
> >>> +.I ptrace_syscall_info
> >>> +structure contains the following fields:
> >>> +.IP
> >>> +.in
> >>> +.EX
> >>> +struct ptrace_syscall_info {
> >>> +    __u8 op;                    /* PTRACE_SYSCALL_INFO_* value
> >>> +                                   describing the kind
> >>> +                                   of system call stop,
> >>> +                                   see <linux/ptrace.h> */
> >>> +    __u32 arch;                 /* AUDIT_ARCH_* value,
> >>> +                                   see seccomp(2) */
> >>> +    __u64 instruction_pointer;  /* CPU instruction pointer */
> >>> +    __u64 stack_pointer;        /* CPU stack pointer */
> >>> +    union {
> >>> +        struct {
> >>> +            __u64 nr;           /* System call number */
> >>> +            __u64 args[6];      /* System call arguments */
> >>> +        } entry;                /* Information specific to
> >>> +                                   system call entry stops */
> >>> +        struct {
> >>> +            __s64 rval;         /* System call return value */
> >>> +            __u8 is_error;      /* System call error flag */
> >>> +        } exit;                 /* Information specific to
> >>> +                                   system call exit stops */
> >>> +        struct {
> >>> +            __u64 nr;           /* System call number */
> >>> +            __u64 args[6];      /* System call arguments */
> >>> +            __u32 ret_data;     /* The SECCOMP_RET_DATA portion
> >>> +                                   of SECCOMP_RET_TRACE return
> >>> +                                   value */
> >>> +        } seccomp;              /* Information specific to
> >>> +                                   PTRACE_EVENT_SECCOMP stops */
> >>> +    };
> >>> +};
> >>> +.EE
> >>> +.in
> >>> +.IP
> >>> +.IR op ,
> >>> +.IR arch ,
> >>> +.IR instruction_pointer ,
> >>> +and
> >>> +.I stack_pointer
> >>> +fields are defined for all kinds of ptrace system call stops.
> >>> +The rest of the structure is a union, one should read only those fields
> >>> +that are meaningful for the kind of system call stop specified by the
> >>> +.IR op
> >>> +field.
> >>>  .\"
> >>>  .SS Death under ptrace
> >>>  When a (possibly multithreaded) process receives a killing signal
> >>
> >> Thanks. I've applied, and done some light editing.
> >>
> >> I also added some pieces. Could you please take a look at commits
> >> f04534d22c69 [1] and 227a3682312 [2] let me know if they are okay.
> > 
> > Thanks.  The only thing that needs correction is
> > "Boolean: is rval != 0?" comment about is_error field.
> > 
> > In fact, is_error is a boolean that tells whether rval field
> > contains a non-error return value (e.g. file descriptor) or
> > an error value (e.g. -ERRORCODE).
> 
> Thanks for checking this Dmitry. I see what I missed before.
> I've now changed the text here to be:
> 
>             __u8 is_error;     /* System call error flag;
>                                   Boolean: does rval contain
>                                   an error value (\-ERRCODE) or
>                                   a nonerror return value? */

Yes, that's better, thanks.


-- 
ldv

^ permalink raw reply	[flat|nested] 7+ messages in thread

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Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-09-02 12:38 [PATCH] ptrace.2: document PTRACE_GET_SYSCALL_INFO Dmitry V. Levin
2019-09-10 10:51 ` Michael Kerrisk (man-pages)
2019-09-11 17:38   ` [PATCH] ptrace.2: document struct ptrace_syscall_info Dmitry V. Levin
2019-09-12  9:17     ` Michael Kerrisk (man-pages)
2019-09-13 15:40       ` Dmitry V. Levin
2019-09-13 18:48         ` Michael Kerrisk (man-pages)
2019-09-13 19:37           ` Dmitry V. Levin

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	git clone --mirror https://lore.kernel.org/linux-man/0 linux-man/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-man linux-man/ https://lore.kernel.org/linux-man \
		linux-man@vger.kernel.org linux-man@archiver.kernel.org
	public-inbox-index linux-man


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-man


AGPL code for this site: git clone https://public-inbox.org/ public-inbox