Tobias Klauser (Gerrit)

unread,

Nov 13, 2025, 4:28:35 AM11/13/25

to Michael Pratt, Michael Knyszek, goph...@pubsubhelper.golang.org, golang-co...@googlegroups.com

Attention needed from Michael Knyszek and Michael Pratt

Tobias Klauser has uploaded the change for review

Tobias Klauser would like Michael Pratt and Michael Knyszek to review this change.

Commit message

unix: add IoctlSetString on all platforms

Currently, only solaris provides IoctlSetString. However, it might be
useful on other platforms too, e.g. for SIOCBRADDBR on linux.

Change-Id: I19ed47a3e4ed0180ba6777bc193e32bfb61c0506

Change diff

diff --git a/unix/ioctl_signed.go b/unix/ioctl_signed.go
index 5b0759b..be0f3fb 100644
--- a/unix/ioctl_signed.go
+++ b/unix/ioctl_signed.go
@@ -6,9 +6,7 @@
 
 package unix
 
-import (
-	"unsafe"
-)
+import "unsafe"
 
 // ioctl itself should not be exposed directly, but additional get/set
 // functions for specific types are permissible.
@@ -28,6 +26,13 @@
 	return ioctlPtr(fd, req, unsafe.Pointer(&v))
 }
 
+// IoctlSetString performs an ioctl operation which sets a string value
+// on fd, using the specified request number.
+func IoctlSetString(fd int, req int, value string) error {
+	bs := append([]byte(value), 0)
+	return ioctlPtr(fd, req, unsafe.Pointer(&bs[0]))
+}
+
 // IoctlSetWinsize performs an ioctl on fd with a *Winsize argument.
 //
 // To change fd's window size, the req argument should be TIOCSWINSZ.
diff --git a/unix/ioctl_unsigned.go b/unix/ioctl_unsigned.go
index 20f470b..f0c2821 100644
--- a/unix/ioctl_unsigned.go
+++ b/unix/ioctl_unsigned.go
@@ -6,9 +6,7 @@
 
 package unix
 
-import (
-	"unsafe"
-)
+import "unsafe"
 
 // ioctl itself should not be exposed directly, but additional get/set
 // functions for specific types are permissible.
@@ -28,6 +26,13 @@
 	return ioctlPtr(fd, req, unsafe.Pointer(&v))
 }
 
+// IoctlSetString performs an ioctl operation which sets a string value
+// on fd, using the specified request number.
+func IoctlSetString(fd int, req uint, value string) error {
+	bs := append([]byte(value), 0)
+	return ioctlPtr(fd, req, unsafe.Pointer(&bs[0]))
+}
+
 // IoctlSetWinsize performs an ioctl on fd with a *Winsize argument.
 //
 // To change fd's window size, the req argument should be TIOCSWINSZ.
diff --git a/unix/syscall_solaris.go b/unix/syscall_solaris.go
index 18a3d9b..a6a2ea0 100644
--- a/unix/syscall_solaris.go
+++ b/unix/syscall_solaris.go
@@ -1052,14 +1052,6 @@
 	return ioctlRet(fd, req, uintptr(arg))
 }
 
-func IoctlSetString(fd int, req int, val string) error {
-	bs := make([]byte, len(val)+1)
-	copy(bs[:len(bs)-1], val)
-	err := ioctlPtr(fd, req, unsafe.Pointer(&bs[0]))
-	runtime.KeepAlive(&bs[0])
-	return err
-}
-
 // Lifreq Helpers
 
 func (l *Lifreq) SetName(name string) error {

Change information

Files:

M unix/ioctl_signed.go
M unix/ioctl_unsigned.go
M unix/syscall_solaris.go

Change size: S

Delta: 3 files changed, 16 insertions(+), 14 deletions(-)

Open in Gerrit

Related details

Attention is currently required from:

Michael Knyszek
Michael Pratt

Submit Requirements:

Code-Review
No-Unresolved-Comments
Review-Enforcement
TryBots-Pass

Inspect html for hidden footers to help with email filtering. To unsubscribe visit settings.

Gerrit

unsatisfied_requirement

satisfied_requirement

open

diffy

Ingo Oeser (Gerrit)

unread,

Nov 13, 2025, 5:45:19 AM11/13/25

to Tobias Klauser, goph...@pubsubhelper.golang.org, Go LUCI, Michael Knyszek, Michael Pratt, golang-co...@googlegroups.com

Attention needed from Michael Knyszek, Michael Pratt and Tobias Klauser

Ingo Oeser added 1 comment

File unix/ioctl_signed.go

Line 32, Patchset 1 (Latest): bs := append([]byte(value), 0)

Ingo Oeser . unresolved

Wouldn't a new string use a bit less memory here and be simpler code?
Same in the other file as well.


```suggestion
	bs := value + "\x00"
```

Open in Gerrit

Related details

Attention is currently required from:

Michael Knyszek
Michael Pratt
Tobias Klauser

Submit Requirements:

Code-Review

No-Unresolved-Comments

Review-Enforcement

TryBots-Pass

Inspect html for hidden footers to help with email filtering. To unsubscribe visit settings.

Gerrit

unsatisfied_requirement

satisfied_requirement

open

diffy

Tobias Klauser (Gerrit)

unread,

Nov 14, 2025, 4:19:33 AM11/14/25

to goph...@pubsubhelper.golang.org, Ingo Oeser, Go LUCI, Michael Knyszek, Michael Pratt, golang-co...@googlegroups.com

Attention needed from Ingo Oeser, Michael Knyszek and Michael Pratt

Tobias Klauser added 1 comment

File unix/ioctl_signed.go

Line 32, Patchset 1 (Latest): bs := append([]byte(value), 0)

Ingo Oeser . resolved

Wouldn't a new string use a bit less memory here and be simpler code?
Same in the other file as well.
```suggestion
	bs := value + "\x00"
```

Tobias Klauser

I'm not sure how this will use less memory as we'd still create a new string.

As I see it, NULL-terminated byte slices/arrays are more natural for interactions with syscalls as strings are just NULL-terminated byte arrays in C APIs. So I think I'd prefer to keep it that way unless there is a strong reason to use a Go string here.

Open in Gerrit

Related details

Attention is currently required from:

Ingo Oeser
Michael Knyszek
Michael Pratt

Submit Requirements:

Code-Review

No-Unresolved-Comments

Review-Enforcement
TryBots-Pass

Inspect html for hidden footers to help with email filtering. To unsubscribe visit settings.

Gerrit

unsatisfied_requirement

satisfied_requirement

open

diffy

Tobias Klauser (Gerrit)

unread,

Nov 26, 2025, 7:05:49 AM11/26/25

to goph...@pubsubhelper.golang.org, Cherry Mui, Ingo Oeser, Go LUCI, Michael Knyszek, Michael Pratt, golang-co...@googlegroups.com

Attention needed from Cherry Mui, Ingo Oeser, Michael Knyszek and Michael Pratt

Tobias Klauser voted

Auto-Submit	+1
Commit-Queue	+1

Open in Gerrit

Related details

Attention is currently required from:

Cherry Mui

Ingo Oeser
Michael Knyszek
Michael Pratt

Submit Requirements:

Code-Review
No-Unresolved-Comments
Review-Enforcement

TryBots-Pass

Inspect html for hidden footers to help with email filtering. To unsubscribe visit settings.

Gerrit

unsatisfied_requirement

satisfied_requirement

open

diffy

Ian Lance Taylor (Gerrit)

unread,

Jan 14, 2026, 6:15:41 PM (3 days ago) Jan 14

to Tobias Klauser, goph...@pubsubhelper.golang.org, Ian Lance Taylor, Go LUCI, Cherry Mui, Ingo Oeser, Michael Knyszek, Michael Pratt, golang-co...@googlegroups.com

Attention needed from Cherry Mui, Ingo Oeser, Michael Knyszek, Michael Pratt and Tobias Klauser

Ian Lance Taylor voted and added 1 comment

Votes added by Ian Lance Taylor

Code-Review

+2

1 comment

Patchset-level comments

File-level comment, Patchset 3 (Latest):

Ian Lance Taylor . resolved

Thanks.

Open in Gerrit

Related details

Attention is currently required from:

Cherry Mui
Ingo Oeser
Michael Knyszek
Michael Pratt

Tobias Klauser

Submit Requirements:

Code-Review

No-Unresolved-Comments
Review-Enforcement

TryBots-Pass

Inspect html for hidden footers to help with email filtering. To unsubscribe visit settings.

Gerrit

satisfied_requirement

unsatisfied_requirement

open

diffy

Florian Lehner (Gerrit)

unread,

Jan 15, 2026, 7:35:03 AM (2 days ago) Jan 15

to Tobias Klauser, goph...@pubsubhelper.golang.org, Ian Lance Taylor, Go LUCI, Cherry Mui, Ingo Oeser, Michael Knyszek, Michael Pratt, golang-co...@googlegroups.com

Attention needed from Cherry Mui, Ingo Oeser, Michael Knyszek, Michael Pratt and Tobias Klauser

Florian Lehner voted Code-Review+1

Code-Review

+1

Open in Gerrit

Related details

Attention is currently required from:

Cherry Mui
Ingo Oeser
Michael Knyszek
Michael Pratt
Tobias Klauser

Submit Requirements:

Code-Review
No-Unresolved-Comments
Review-Enforcement
TryBots-Pass

Inspect html for hidden footers to help with email filtering. To unsubscribe visit settings.

Gerrit

satisfied_requirement

unsatisfied_requirement

open

diffy

Cherry Mui (Gerrit)

unread,

Jan 15, 2026, 4:59:30 PM (2 days ago) Jan 15

to Tobias Klauser, goph...@pubsubhelper.golang.org, Ian Lance Taylor, Go LUCI, Ingo Oeser, Michael Knyszek, Michael Pratt, golang-co...@googlegroups.com

Attention needed from Ingo Oeser, Michael Knyszek, Michael Pratt and Tobias Klauser

Cherry Mui voted Code-Review+1

Code-Review

+1

Open in Gerrit

Related details

Attention is currently required from:

satisfied_requirement

unsatisfied_requirement

open

diffy

Michael Pratt (Gerrit)

unread,

Jan 16, 2026, 5:09:14 PM (yesterday) Jan 16

to Tobias Klauser, goph...@pubsubhelper.golang.org, Michael Pratt, Cherry Mui, Ian Lance Taylor, Go LUCI, Ingo Oeser, Michael Knyszek, golang-co...@googlegroups.com

Attention needed from Ingo Oeser, Michael Knyszek and Tobias Klauser

Michael Pratt voted Code-Review+1

Code-Review

+1

Open in Gerrit

Related details

Attention is currently required from:

Ingo Oeser
Michael Knyszek
Tobias Klauser

Submit Requirements:

Code-Review
No-Unresolved-Comments

Review-Enforcement
TryBots-Pass

Inspect html for hidden footers to help with email filtering. To unsubscribe visit settings.

Gerrit

satisfied_requirement

open

diffy

Gopher Robot (Gerrit)

unread,

Jan 16, 2026, 5:09:52 PM (yesterday) Jan 16

to Tobias Klauser, goph...@pubsubhelper.golang.org, golang-...@googlegroups.com, Michael Pratt, Cherry Mui, Ian Lance Taylor, Go LUCI, Ingo Oeser, Michael Knyszek, golang-co...@googlegroups.com

Gopher Robot submitted the change

Change information

Commit message:

unix: add IoctlSetString on all platforms

Currently, only solaris provides IoctlSetString. However, it might be
useful on other platforms too, e.g. for SIOCBRADDBR on linux.

Change-Id: I19ed47a3e4ed0180ba6777bc193e32bfb61c0506

Reviewed-on: https://go-review.googlesource.com/c/sys/+/720200

Reviewed-by: Michael Pratt <mpr...@google.com>

Reviewed-by: Ian Lance Taylor <ia...@golang.org>

Reviewed-by: Florian Lehner <lehner.f...@gmail.com>

LUCI-TryBot-Result: Go LUCI <golang...@luci-project-accounts.iam.gserviceaccount.com>

Auto-Submit: Tobias Klauser <tobias....@gmail.com>

Reviewed-by: Cherry Mui <cher...@google.com>

Files:

M unix/ioctl_signed.go
M unix/ioctl_unsigned.go
M unix/syscall_solaris.go

Change size: S

Delta: 3 files changed, 16 insertions(+), 14 deletions(-)

Branch: refs/heads/master

Submit Requirements:

Code-Review: +1 by Michael Pratt, +1 by Florian Lehner, +1 by Cherry Mui, +2 by Ian Lance Taylor
TryBots-Pass: LUCI-TryBot-Result+1 by Go LUCI

Open in Gerrit

Inspect html for hidden footers to help with email filtering. To unsubscribe visit settings.

Gerrit

open

diffy

satisfied_requirement

Reply all

Reply to author

Forward

[sys] unix: add IoctlSetString on all platforms

Tobias Klauser (Gerrit)

Tobias Klauser has uploaded the change for review

Commit message

Change diff

Change information

Related details

Ingo Oeser (Gerrit)

Ingo Oeser added 1 comment

Related details

Tobias Klauser (Gerrit)

Tobias Klauser added 1 comment

Related details

Tobias Klauser (Gerrit)

Tobias Klauser voted

Related details

Ian Lance Taylor (Gerrit)

Ian Lance Taylor voted and added 1 comment

Votes added by Ian Lance Taylor

1 comment

Related details

Florian Lehner (Gerrit)

Florian Lehner voted Code-Review+1

Related details

Cherry Mui (Gerrit)

Cherry Mui voted Code-Review+1

Related details

Michael Pratt (Gerrit)

Michael Pratt voted Code-Review+1

Related details

Gopher Robot (Gerrit)

Gopher Robot submitted the change

Change information