# Wip\_write returns -1 **URL:** \ **Category:** Open AT\ **Created:** [July 24, 2014, 11:58am UTC](https://forum.sierrawireless.com/t/wip-write-returns-1/7336 "2014-07-24T11:58:53Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![mandy](https://avatars.discourse-cdn.com/v4/letter/m/b4bc9f/32.png) [@mandy](https://forum.sierrawireless.com/u/mandy)\ **Post date:** [July 24, 2014, 11:58am UTC](https://forum.sierrawireless.com/t/wip-write-returns-1/7336/1 "2014-07-24T11:58:53Z")
Hello, I try to write to an SSL socket more than 5000 bytes. The wip\_write function returns as error code -1. This is not described in the help. What does -1 means in this case? Writing less than 5000 bytes, it succeed. Why it is not possible to write more than 5000 bytes? I excpect, that the write function would return the number of bytes actually written bytes and I have to use the wip\_write funtion again. But instead of thi sit retunrs -1. ---
**Author:** ![Rex\_alex](https://avatars.discourse-cdn.com/v4/letter/r/73ab20/32.png) [@Rex\_alex](https://forum.sierrawireless.com/u/Rex_alex)\ **Post date:** [July 30, 2014, 1:39pm UTC](https://forum.sierrawireless.com/t/wip-write-returns-1/7336/2 "2014-07-30T13:39:17Z")
Strange… Never tried this before… but yes, the error -1 is not documented… need to check is it a limitation or not… i’ll test it and keep you updated… ---
**Author:** ![mandy](https://avatars.discourse-cdn.com/v4/letter/m/b4bc9f/32.png) [@mandy](https://forum.sierrawireless.com/u/mandy)\ **Post date:** [July 31, 2014, 6:04am UTC](https://forum.sierrawireless.com/t/wip-write-returns-1/7336/3 "2014-07-31T06:04:02Z")
So far I closed the socket after an write error. Now I don’t do it and see, that after the wip\_write returned -1 the WIP\_CEV\_WRITE event is raised again and I am able to write more than 5000 bytes (even 10000 bytes). - WIP\_CEV\_WRITE event - wip\_write(socket, buffer, 10000) --\> -1 - WIP\_CEV\_WRITE event - wip\_write(socket, buffer, 10000) --\> successfully written 10000 bytes ---
**Author:** ![mandy](https://avatars.discourse-cdn.com/v4/letter/m/b4bc9f/32.png) [@mandy](https://forum.sierrawireless.com/u/mandy)\ **Post date:** [August 13, 2014, 8:31am UTC](https://forum.sierrawireless.com/t/wip-write-returns-1/7336/4 "2014-08-13T08:31:26Z")
Now I checked the WIP\_COPT\_SND\_BUFSIZE with the wip\_getOpts function. It is set to 5.840. The size of my buffer is 10.000. So it is not surprising, that the writing failed. But why it fails with -1. Writing also fails with -1, after reducing my buffer to 5814. A buffer of 5776 bytes, can be successfully written the first time. After the next WIP\_CEV\_WRITE event wip\_writes fails with -1. I tried to increase the send buffer size. But the wip\_setOpts fails with -1, whether I set the buffer to more than 5840 bytes or the buffer is smaller than 5840 bytes. ---
**Author:** ![Rex\_alex](https://avatars.discourse-cdn.com/v4/letter/r/73ab20/32.png) [@Rex\_alex](https://forum.sierrawireless.com/u/Rex_alex)\ **Post date:** [August 13, 2014, 2:02pm UTC](https://forum.sierrawireless.com/t/wip-write-returns-1/7336/5 "2014-08-13T14:02:30Z")
Hi, can u share the piece of code? ---
**Author:** ![mandy](https://avatars.discourse-cdn.com/v4/letter/m/b4bc9f/32.png) [@mandy](https://forum.sierrawireless.com/u/mandy)\ **Post date:** [August 13, 2014, 2:17pm UTC](https://forum.sierrawireless.com/t/wip-write-returns-1/7336/6 "2014-08-13T14:17:02Z")
Here wip\_write returns -1 ```auto static u8 snd_buffer[BUFFER_SIZE]; static u8 snd_buffer2[BUFFER_SIZE]; case WIP_CEV_WRITE: { int nwrite; TRACE((2, "(evh): WIP_CEV_WRITE: Can send more data")); if (snd_length > 0) { TRACE((2, "(evh): WIP_CEV_WRITE: Trying to send %d Bytes of Data (%d)", snd_length, writeErrors)); nwrite = wip_write(channel, snd_buffer, snd_length); if (nwrite >= 0) { TRACE((2, "(evh): WIP_CEV_WRITE: Written %d Bytes", nwrite)); snd_length -= nwrite; TRACE((1, "%d bytes written to the server (%d still need to be sent)", nwrite, snd_length)); wm_memcpy(snd_buffer2, snd_buffer + nwrite, snd_length); wm_memcpy(snd_buffer, snd_buffer2, snd_length); } else { writeErrors++; TRACE((1, "ERROR: (evh): WIP_CEV_WRITE: Write Error: %d (%d)", nwrite, writeErrors)); switch (nwrite) { case WIP_CERR_CSTATE: TRACE((1, "ERROR: could not write to the server, because channel is not ready to write data (still in initialization, or is already closed)")); break; case WIP_CERR_NOT_SUPPORTED: TRACE((1, "ERROR: could not write to the server, because the channel does not support data writing")); break; default: TRACE((1, "ERROR: could not write to the server")); break; } send_allowed = 0; } } else { TRACE((2, "(evh): WIP_CEV_WRITE: Nothing to send")); TRACE((1, "Nothing to send")); } } ``` Here wip\_setOpts returns -1 ```auto UINT32 sndBufSize = 1000; UINT32 sndLowAt = 0; BOOL noDelay = TRUE; INT8 ret; ret = wip_setOpts(socket, WIP_COPT_SND_BUFSIZE, sndBufSize, WIP_COPT_SND_LOWAT, sndLowAt, WIP_COPT_NODELAY, noDelay, WIP_COPT_END); ``` ---
**Author:** ![Rex\_alex](https://avatars.discourse-cdn.com/v4/letter/r/73ab20/32.png) [@Rex\_alex](https://forum.sierrawireless.com/u/Rex_alex)\ **Post date:** [September 17, 2014, 1:02pm UTC](https://forum.sierrawireless.com/t/wip-write-returns-1/7336/7 "2014-09-17T13:02:00Z")
i tried the sample code what we have… i am not facing any issues… if i try to write the data more than the snd buffer size… the write event is coming… which FW … module are you using? ---
**Author:** ![mandy](https://avatars.discourse-cdn.com/v4/letter/m/b4bc9f/32.png) [@mandy](https://forum.sierrawireless.com/u/mandy)\ **Post date:** [September 17, 2014, 1:27pm UTC](https://forum.sierrawireless.com/t/wip-write-returns-1/7336/8 "2014-09-17T13:27:20Z")
I’m using the module FXT009 with the firmware 7.52.0.201404040850 (Internet Library Package Version 5.56.0.201305170830; Security Library Package Version 2.2.0.201306261000). What do you mean with ‘the write event is coming’? The WIP\_CEV\_WRITE event? The WIP\_CEV\_WRITE is received in the event handler. wip\_write(channel, large\_buffer, 10000); returns -1. The WIP\_CEV\_WRITE event is coming again after wip\_write failed. After several mistrials with wip\_write, the wip\_write function returns the successfully written number of bytes.