AIX 7.2 TL3, Go version 1.14.2:

# oslevel -s
7200-03-02-1846

# rpm -qa | grep golang
golang-1.14.2-1.ppc
golang-src-1.14.2-1.noarch
golang-bin-1.14.2-1.ppc

Very simple example with os.OpenFile() and Sync():

package main

import (
  "fmt"
  "os"
)

func main() {
  f, err := os.OpenFile("/tmp/1", os.O_RDONLY, 0644)
  if err != nil {
    fmt.Printf("os.OpenFile: %s\n", err)
    return
  }
  defer f.Close()

  err = f.Sync()
  if err != nil {
    fmt.Printf("os.Sync(): %s\n", err)
    pe, ok := err.(*os.PathError)
    if ok {
      fmt.Printf("Op: %s, Path: %s, Err: %v\n", pe.Op, pe.Path, pe.Err)
    } else {
      fmt.Printf("not ok to PathError\n")
    }
  }
}

No Problems on Linux and Mac OS X, but on AIX:

os.Sync(): sync /tmp/1: bad file number
Op: sync, Path: /tmp/1, Err: bad file number

I think, sync() is quite usual function and should work ;-)

------------------------------
Andrey Klyachkin
------------------------------

#AIXOpenSource

Hi Andrey, 

The problem is that AIX fsync syscall fails when a file is open in Read-Only mode. 
From "man fsync":
 Note: The file identified by the FileDescriptor parameter must be open for writing when the fsync subroutine
is issued or the call is unsuccessful. This restriction was not enforced in BSD systems. The fsync_range
subroutine does not require write access.

Maybe fsync_range can be called instead of fsync. I'll check that.
Meanwhile, could you open an issue in Golang github (https://github.com/golang/go) ? That way, the community and not only us can answer. 

Thanks
Clément

------------------------------
Clement CHIGOT
------------------------------

Original Message:
Sent: Fri September 11, 2020 09:58 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

AIX 7.2 TL3, Go version 1.14.2:

# oslevel -s
7200-03-02-1846

# rpm -qa | grep golang
golang-1.14.2-1.ppc
golang-src-1.14.2-1.noarch
golang-bin-1.14.2-1.ppc

Very simple example with os.OpenFile() and Sync():

package main

import (
  "fmt"
  "os"
)

func main() {
  f, err := os.OpenFile("/tmp/1", os.O_RDONLY, 0644)
  if err != nil {
    fmt.Printf("os.OpenFile: %s\n", err)
    return
  }
  defer f.Close()

  err = f.Sync()
  if err != nil {
    fmt.Printf("os.Sync(): %s\n", err)
    pe, ok := err.(*os.PathError)
    if ok {
      fmt.Printf("Op: %s, Path: %s, Err: %v\n", pe.Op, pe.Path, pe.Err)
    } else {
      fmt.Printf("not ok to PathError\n")
    }
  }
}

No Problems on Linux and Mac OS X, but on AIX:

os.Sync(): sync /tmp/1: bad file number
Op: sync, Path: /tmp/1, Err: bad file number

I think, sync() is quite usual function and should work ;-)

------------------------------
Andrey Klyachkin
------------------------------

#AIXOpenSource

Thank you Clément for the pointing out to the man! If I change to O_RDWR, it works. I opened the issue on github - https://github.com/golang/go/issues/41372

------------------------------
Andrey Klyachkin
------------------------------

Original Message:
Sent: Mon September 14, 2020 03:58 AM
From: Clement CHIGOT
Subject: golang Sync() error on AIX

Hi Andrey, 

The problem is that AIX fsync syscall fails when a file is open in Read-Only mode. 
From "man fsync":
 Note: The file identified by the FileDescriptor parameter must be open for writing when the fsync subroutine
is issued or the call is unsuccessful. This restriction was not enforced in BSD systems. The fsync_range
subroutine does not require write access.

Maybe fsync_range can be called instead of fsync. I'll check that.
Meanwhile, could you open an issue in Golang github (https://github.com/golang/go) ? That way, the community and not only us can answer. 

Thanks
Clément

------------------------------
Clement CHIGOT

Original Message:
Sent: Fri September 11, 2020 09:58 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

AIX 7.2 TL3, Go version 1.14.2:

# oslevel -s
7200-03-02-1846

# rpm -qa | grep golang
golang-1.14.2-1.ppc
golang-src-1.14.2-1.noarch
golang-bin-1.14.2-1.ppc

Very simple example with os.OpenFile() and Sync():

package main

import (
  "fmt"
  "os"
)

func main() {
  f, err := os.OpenFile("/tmp/1", os.O_RDONLY, 0644)
  if err != nil {
    fmt.Printf("os.OpenFile: %s\n", err)
    return
  }
  defer f.Close()

  err = f.Sync()
  if err != nil {
    fmt.Printf("os.Sync(): %s\n", err)
    pe, ok := err.(*os.PathError)
    if ok {
      fmt.Printf("Op: %s, Path: %s, Err: %v\n", pe.Op, pe.Path, pe.Err)
    } else {
      fmt.Printf("not ok to PathError\n")
    }
  }
}

No Problems on Linux and Mac OS X, but on AIX:

os.Sync(): sync /tmp/1: bad file number
Op: sync, Path: /tmp/1, Err: bad file number

I think, sync() is quite usual function and should work ;-)

------------------------------
Andrey Klyachkin
------------------------------

#AIXOpenSource

You are doing Sync() on a read only file descriptor which is not allowed.
May be in Linux, it silently ignores it without throwing any error.

------------------------------
Ayappan P
------------------------------

Original Message:
Sent: Fri September 11, 2020 09:58 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

AIX 7.2 TL3, Go version 1.14.2:

# oslevel -s
7200-03-02-1846

# rpm -qa | grep golang
golang-1.14.2-1.ppc
golang-src-1.14.2-1.noarch
golang-bin-1.14.2-1.ppc

Very simple example with os.OpenFile() and Sync():

package main

import (
  "fmt"
  "os"
)

func main() {
  f, err := os.OpenFile("/tmp/1", os.O_RDONLY, 0644)
  if err != nil {
    fmt.Printf("os.OpenFile: %s\n", err)
    return
  }
  defer f.Close()

  err = f.Sync()
  if err != nil {
    fmt.Printf("os.Sync(): %s\n", err)
    pe, ok := err.(*os.PathError)
    if ok {
      fmt.Printf("Op: %s, Path: %s, Err: %v\n", pe.Op, pe.Path, pe.Err)
    } else {
      fmt.Printf("not ok to PathError\n")
    }
  }
}

No Problems on Linux and Mac OS X, but on AIX:

os.Sync(): sync /tmp/1: bad file number
Op: sync, Path: /tmp/1, Err: bad file number

I think, sync() is quite usual function and should work ;-)

------------------------------
Andrey Klyachkin
------------------------------

#AIXOpenSource

we usually use high-level languages instead of C, because the function the same or similar way on all platforms. If it is silently ignored on Linux, it should be  ignored on AIX too. AFAIU the golang runtime (syscalls package?) should be changed to make it possible.

------------------------------
Andrey Klyachkin
------------------------------

Original Message:
Sent: Mon September 14, 2020 03:58 AM
From: Ayappan P
Subject: golang Sync() error on AIX

You are doing Sync() on a read only file descriptor which is not allowed.
May be in Linux, it silently ignores it without throwing any error.

------------------------------
Ayappan P

Original Message:
Sent: Fri September 11, 2020 09:58 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

AIX 7.2 TL3, Go version 1.14.2:

# oslevel -s
7200-03-02-1846

# rpm -qa | grep golang
golang-1.14.2-1.ppc
golang-src-1.14.2-1.noarch
golang-bin-1.14.2-1.ppc

Very simple example with os.OpenFile() and Sync():

package main

import (
  "fmt"
  "os"
)

func main() {
  f, err := os.OpenFile("/tmp/1", os.O_RDONLY, 0644)
  if err != nil {
    fmt.Printf("os.OpenFile: %s\n", err)
    return
  }
  defer f.Close()

  err = f.Sync()
  if err != nil {
    fmt.Printf("os.Sync(): %s\n", err)
    pe, ok := err.(*os.PathError)
    if ok {
      fmt.Printf("Op: %s, Path: %s, Err: %v\n", pe.Op, pe.Path, pe.Err)
    } else {
      fmt.Printf("not ok to PathError\n")
    }
  }
}

No Problems on Linux and Mac OS X, but on AIX:

os.Sync(): sync /tmp/1: bad file number
Op: sync, Path: /tmp/1, Err: bad file number

I think, sync() is quite usual function and should work ;-)

------------------------------
Andrey Klyachkin
------------------------------

#AIXOpenSource

Linux doesn't have this restriction. Thus, there is no "silent error", it works.
However, using fsync_range(fd, O_SYNC, 0, 0) seems to have the same behavior and will work for every opened files included read-only ones. I'll send the patch to the community (once I'm sure it isn't breaking anything), and I suppose it can be backported easily to older versions.

Thanks for the issue. 

------------------------------
Clement CHIGOT
------------------------------

Original Message:
Sent: Mon September 14, 2020 04:26 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

we usually use high-level languages instead of C, because the function the same or similar way on all platforms. If it is silently ignored on Linux, it should be  ignored on AIX too. AFAIU the golang runtime (syscalls package?) should be changed to make it possible.

------------------------------
Andrey Klyachkin

Original Message:
Sent: Mon September 14, 2020 03:58 AM
From: Ayappan P
Subject: golang Sync() error on AIX

You are doing Sync() on a read only file descriptor which is not allowed.
May be in Linux, it silently ignores it without throwing any error.

------------------------------
Ayappan P

Original Message:
Sent: Fri September 11, 2020 09:58 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

AIX 7.2 TL3, Go version 1.14.2:

# oslevel -s
7200-03-02-1846

# rpm -qa | grep golang
golang-1.14.2-1.ppc
golang-src-1.14.2-1.noarch
golang-bin-1.14.2-1.ppc

Very simple example with os.OpenFile() and Sync():

package main

import (
  "fmt"
  "os"
)

func main() {
  f, err := os.OpenFile("/tmp/1", os.O_RDONLY, 0644)
  if err != nil {
    fmt.Printf("os.OpenFile: %s\n", err)
    return
  }
  defer f.Close()

  err = f.Sync()
  if err != nil {
    fmt.Printf("os.Sync(): %s\n", err)
    pe, ok := err.(*os.PathError)
    if ok {
      fmt.Printf("Op: %s, Path: %s, Err: %v\n", pe.Op, pe.Path, pe.Err)
    } else {
      fmt.Printf("not ok to PathError\n")
    }
  }
}

No Problems on Linux and Mac OS X, but on AIX:

os.Sync(): sync /tmp/1: bad file number
Op: sync, Path: /tmp/1, Err: bad file number

I think, sync() is quite usual function and should work ;-)

------------------------------
Andrey Klyachkin
------------------------------
#AIXOpenSource

The patch have been accepted by the community https://go-review.googlesource.com/c/go/+/254657/. 
@Andrey Klyachkin you can either download and compile the master, or wait a little for AIXToolbox or BullFreeware to release the new version with the fix.

Clément​

------------------------------
Clement CHIGOT
------------------------------

Original Message:
Sent: Mon September 14, 2020 06:34 AM
From: Clement CHIGOT
Subject: golang Sync() error on AIX

Linux doesn't have this restriction. Thus, there is no "silent error", it works.
However, using fsync_range(fd, O_SYNC, 0, 0) seems to have the same behavior and will work for every opened files included read-only ones. I'll send the patch to the community (once I'm sure it isn't breaking anything), and I suppose it can be backported easily to older versions.

Thanks for the issue. 

------------------------------
Clement CHIGOT

Original Message:
Sent: Mon September 14, 2020 04:26 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

we usually use high-level languages instead of C, because the function the same or similar way on all platforms. If it is silently ignored on Linux, it should be  ignored on AIX too. AFAIU the golang runtime (syscalls package?) should be changed to make it possible.

------------------------------
Andrey Klyachkin

Original Message:
Sent: Mon September 14, 2020 03:58 AM
From: Ayappan P
Subject: golang Sync() error on AIX

You are doing Sync() on a read only file descriptor which is not allowed.
May be in Linux, it silently ignores it without throwing any error.

------------------------------
Ayappan P

Original Message:
Sent: Fri September 11, 2020 09:58 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

AIX 7.2 TL3, Go version 1.14.2:

# oslevel -s
7200-03-02-1846

# rpm -qa | grep golang
golang-1.14.2-1.ppc
golang-src-1.14.2-1.noarch
golang-bin-1.14.2-1.ppc

Very simple example with os.OpenFile() and Sync():

package main

import (
  "fmt"
  "os"
)

func main() {
  f, err := os.OpenFile("/tmp/1", os.O_RDONLY, 0644)
  if err != nil {
    fmt.Printf("os.OpenFile: %s\n", err)
    return
  }
  defer f.Close()

  err = f.Sync()
  if err != nil {
    fmt.Printf("os.Sync(): %s\n", err)
    pe, ok := err.(*os.PathError)
    if ok {
      fmt.Printf("Op: %s, Path: %s, Err: %v\n", pe.Op, pe.Path, pe.Err)
    } else {
      fmt.Printf("not ok to PathError\n")
    }
  }
}

No Problems on Linux and Mac OS X, but on AIX:

os.Sync(): sync /tmp/1: bad file number
Op: sync, Path: /tmp/1, Err: bad file number

I think, sync() is quite usual function and should work ;-)

------------------------------
Andrey Klyachkin
------------------------------
#AIXOpenSource

Thank you @Clement CHIGOT! ​

------------------------------
Andrey Klyachkin
------------------------------

Original Message:
Sent: Tue September 15, 2020 04:47 AM
From: Clement CHIGOT
Subject: golang Sync() error on AIX

The patch have been accepted by the community https://go-review.googlesource.com/c/go/+/254657/. 
@Andrey Klyachkin you can either download and compile the master, or wait a little for AIXToolbox or BullFreeware to release the new version with the fix.

Clément​

------------------------------
Clement CHIGOT

Original Message:
Sent: Mon September 14, 2020 06:34 AM
From: Clement CHIGOT
Subject: golang Sync() error on AIX

Linux doesn't have this restriction. Thus, there is no "silent error", it works.
However, using fsync_range(fd, O_SYNC, 0, 0) seems to have the same behavior and will work for every opened files included read-only ones. I'll send the patch to the community (once I'm sure it isn't breaking anything), and I suppose it can be backported easily to older versions.

Thanks for the issue. 

------------------------------
Clement CHIGOT

Original Message:
Sent: Mon September 14, 2020 04:26 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

we usually use high-level languages instead of C, because the function the same or similar way on all platforms. If it is silently ignored on Linux, it should be  ignored on AIX too. AFAIU the golang runtime (syscalls package?) should be changed to make it possible.

------------------------------
Andrey Klyachkin

Original Message:
Sent: Mon September 14, 2020 03:58 AM
From: Ayappan P
Subject: golang Sync() error on AIX

You are doing Sync() on a read only file descriptor which is not allowed.
May be in Linux, it silently ignores it without throwing any error.

------------------------------
Ayappan P

Original Message:
Sent: Fri September 11, 2020 09:58 AM
From: Andrey Klyachkin
Subject: golang Sync() error on AIX

AIX 7.2 TL3, Go version 1.14.2:

# oslevel -s
7200-03-02-1846

# rpm -qa | grep golang
golang-1.14.2-1.ppc
golang-src-1.14.2-1.noarch
golang-bin-1.14.2-1.ppc

Very simple example with os.OpenFile() and Sync():

package main

import (
  "fmt"
  "os"
)

func main() {
  f, err := os.OpenFile("/tmp/1", os.O_RDONLY, 0644)
  if err != nil {
    fmt.Printf("os.OpenFile: %s\n", err)
    return
  }
  defer f.Close()

  err = f.Sync()
  if err != nil {
    fmt.Printf("os.Sync(): %s\n", err)
    pe, ok := err.(*os.PathError)
    if ok {
      fmt.Printf("Op: %s, Path: %s, Err: %v\n", pe.Op, pe.Path, pe.Err)
    } else {
      fmt.Printf("not ok to PathError\n")
    }
  }
}

No Problems on Linux and Mac OS X, but on AIX:

os.Sync(): sync /tmp/1: bad file number
Op: sync, Path: /tmp/1, Err: bad file number

I think, sync() is quite usual function and should work ;-)

------------------------------
Andrey Klyachkin
------------------------------
#AIXOpenSource