In the C/C++ Programmers Guide under Input and Output there is this note: "Avoiding Undesirable Results when Using I/O
File serialization is not provided for different tasks attempting to access the same file. When a C/C++ application is run on one task, and the same application or another C/C++ application is run on a different task, any attempts for both applications to access the same file is the responsibility of the application." So the question then becomes whether or not the multiple Java threads are running on a single TCB or on multiple TCB's. Not being a JVM expert I don't know the answer to that question. I'm AssUMing that your "native C library" is a JNI application, so a second question would be whether JNI applications are allowed/disallowed from being used in multiple threads at the same time. Which is something a Java guru would need to tell you. I know I'm only asking more questions here, but I suspect that going down those roads may lead you to better answers. HTH Peter -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Michael Knigge Sent: Wednesday, June 29, 2016 1:30 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Multithreaded output to stderr and stdout All, I have a multithreaded Java application that writes to stdout (and stderr) thru a native C library using fputc and fwrite. Now, at our site everything is all right with output to stderr and stdout from multiple threads. At a customer site only output from the main thread is written to the "file" if the DD STDOUT (or STDERR) points to a MVS Data Set. All output from the other threads is discarded. If the DD points to SYSOUT=* (instead of a MVS Data Set) the output from the threads is written to the "file" as expected.... Does anyone have an idea why? LE370 settings are equal to the settings at our site... Maybe a special SMS Setting?? I have no idea (and no access to the customer site).... Thank you, Michael -- This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
