How can I write runtime trace information to a buffer instead of to the screen?

You can do it by replacing the default print function with that of your own. The default is fprintf() and stdout. Below is an example which uses ossPrintPER() to print PER encodings on a bit-by-bit basis.

It illustrates the procedure of replacing fprintf() and the stream pointer stdout with those of your own by calling ossSetUserPrint().

Select one of the files to download the example.

The Windows example is a VC++ project zip file that you can run as is. You will need to do some minor adjustments according to your installation of the OSS ASN.1 Tools.

If you target an operating system other than Windows or UNIX, you can also use either of these zip files and discard the Windows- or UNIX-specific files.

The samples included with some of the Knowledge Center answers are meant for your general understanding of the OSS products. Different versions of the products might produce slightly different outputs. Consult the products documentation and samples for the most up-to-date products information and code examples.

Contact Support
contact Our office hours
24 hours/day, 7 days/week

  • Phone: 1-888-OSS-2761 (USA and Canada)
  • Phone: 1-732-302-9669 (International)
  • Fax: 1-732-302-0023
  • Email:
Free Trial

Test drive the OSS Nokalva ASN.1, LTE, and XML Tools now! Your trial includes complete software, documentation, sample programs, free 24x7 technical support and more.

Learn ASN.1
Learn ASN.1

Our expert personnel can help you learn ASN.1!

We offer 4-day ASN.1 courses at our headquarters or your premises.