RE: sftp_read receives EOF on second call for a 24kb file

["Kevin Lambert" <klambert@xxxxxxxxx>]

I just modified my code as such:

 

    size_t count = 0;

    size_t totalLength = 0; 

  char buffer[1024];

  size_t length = sizeof(buffer);

 

    count = sftp_read(file, buffer, length);

 

    while ( count > 0 ) {

 

      if ( destFile.is_open() ) {

        destFile.write(buffer, length);

      }

 

      totalLength += count;

 

      sftp_seek(file, totalLength);

      count = sftp_read(file, buffer, length);

    }

 

But I still end up receiving EOF.

 

From: Darren [mailto:d.tomlin@xxxxxxxxxxxx] 
Sent: Wednesday, October 23, 2013 9:20 AM
To: libssh@xxxxxxxxxx
Subject: Re: sftp_read receives EOF on second call for a 24kb file

 

 

Hi Andreas :o),

Many thanks for LibSSH!

Alas, I believe it is a bug in libssh which is why I came up with that work around.

 I know it's not a great solution but it does work for the time being ;)

-Darren.

 

-----Original Message-----
From: Kevin Lambert <klambert@xxxxxxxxx>
To: libssh@xxxxxxxxxx
Sent: Wed, 23 Oct 2013 13:33
Subject: RE: sftp_read receives EOF on second call for a 24kb file

That is what I was asking about.  I have a 24kb file that I was trying to 
transfer in 1kb chunks, transferred 1kb without a problem but on my second call 
to sftp_read there was a SSH_FX_EOF received at line 1802 in sftp.c (version 
0.5.5).  I built this with openssl 1.0.1.  The reason I sent the ssh_session 
init along with the sftp code was incase there was something I was doing wrong 
in the ssh session initialization to cause this.
 
My read loop is as such:
 
  char buffer[1024];
  size_t length = sizeof(buffer);
  size_t totalLength = 0;
    size_t count = 0;
 
    count = sftp_read(file, buffer, length);
 
    while ( count > 0 ) {
 
      if ( destFile.is_open() ) {
        destFile.write(buffer, length);
      }
 
      totalLength += count;
 
      count = sftp_read(file, buffer, length);
    }
 
Kevin
 
-----Original Message-----
From: Aris Adamantiadis [mailto:aris@xxxxxxxxxxxx <mailto:aris@xxxxxxxxxxxx?> ] 
Sent: Wednesday, October 23, 2013 7:47 AM
To: libssh@xxxxxxxxxx
Subject: Re: sftp_read receives EOF on second call for a 24kb file
 
Hi Andreas,
 
I think Kevin complained that sftp_read returned an EOF condition when the file 
was not fully read, and if it does it's a bug in libssh.
 
Aris
 
Le 23/10/13 09:53, Andreas Schneider a écrit :
> On Tuesday 22 October 2013 18:58:17 Darren wrote:
>>  Hi Kevin,
>> 
>> Assuming remote to local transfer:
>> 
>> You read the first chunk of data, and use sftp_seek to move the file 
>> pointer
>> 
> 
> There is absolutely no need to call sftp_seek() you only need it if 
> you resume a transfer. The API works the same way as the POSIX API. 
> Files should be transferred in small chunks.
> 
> #define MAX_XFER_BUF_SIZE 16384
> 
> char buf[MAX_XFER_BUF_SIZE];
> 
> file = sftp_open(sftp, path, O_RDONLY, 0);
> 
> for (;;) {
>       bytesread = sftp_read(file, buf, MAX_XFER_BUF_SIZE);
>       if (bytesread == 0) {
>              break; /* EOF */
>       } else if (bytesread < 0) {
>              /* ERROR HANDLING */
>       }
> 
>       byteswritten = write(fd, buf, MAX_XFER_BUF_SIZE)
>       if (byteswritten != bytesread) {
>               /* ERROR */
>       }
> }
> 
> This way I can transfer files which are several gigabyte of size.
> 
> 
>       -- andreas
>