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NAME |SYNOPSIS |DESCRIPTION |RETURN VALUE |EXAMPLE |FILES |SEE ALSO |AUTHOR |REPORTING BUGS |LICENSE |RESOURCES |COPYING |NOTES |COLOPHON | |
LIBTRACEFS(3) libtracefs ManualLIBTRACEFS(3)tracefs_binary_init, tracefs_binary_close, tracefs_binary_write - Open, close and write binary data in the trace buffer.
#include <tracefs.h> inttracefs_binary_init(struct tracefs_instance *instance); inttracefs_binary_write(struct tracefs_instance *instance, void *data, intlen); voidtracefs_binary_close(struct tracefs_instance *instance);
Set of functions to write binary data in the trace buffer. See Documentation/trace/ftrace.rst from the Linux kernel tree for more information about writing data from user space in the trace buffer. All these APIs haveinstance as a first argument. If NULL is passed asinstance, the top trace instance is used. Thetracefs_binary_init()function initializes the library for writing into the trace buffer of the selectedinstance. It is not mandatory to call this API before writing data, thetracefs_binary_write()will call it automatically, if the library is not yet initialized. But callingtracefs_binary_init()in advance will speed up the writing. Thetracefs_binary_write()function writes a binary data in the trace buffer of the selectedinstance. Thedata points to the data with lengthlen, that is going to be written in the trace buffer. Thetracefs_binary_close()function closes the resources, used by the library for writing in the trace buffer of the selected instance.
Thetracefs_binary_init(), andtracefs_binary_write()functions return 0 if the operation is successful, or -1 in case of an error.
#include <tracefs.h> if (tracefs_binary_init(NULL) < 0) { /* Failed to initialize the library for writing in the trace buffer of the top trace instance */ } unsigned int data = 0xdeadbeef; if (tracefs_binary_write(NULL, &data, sizeof(data)) < 0) { /* Failed to write in the trace buffer */ } tracefs_binary_close();tracefs.h Header file to include in order to have access to the library APIs.-ltracefs Linker switch to add when building a program that uses the library.
libtracefs(3),libtraceevent(3),trace-cmd(1), Documentation/trace/ftrace.rst from the Linux kernel tree
Steven Rostedt<rostedt@goodmis.org[1]>Tzvetomir Stoyanov<tz.stoyanov@gmail.com[2]>
Report bugs to <linux-trace-devel@vger.kernel.org[3]>
libtracefs is Free Software licensed under the GNU LGPL 2.1
https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/
Copyright (C) 2021 VMware, Inc. Free use of this software is granted under the terms of the GNU Public License (GPL).
1. rostedt@goodmis.org mailto:rostedt@goodmis.org 2. tz.stoyanov@gmail.com mailto:tz.stoyanov@gmail.com 3. linux-trace-devel@vger.kernel.org mailto:linux-trace-devel@vger.kernel.org
This page is part of thelibtracefs (Linux kernel trace file system library) project. Information about the project can be found at ⟨https://www.trace-cmd.org/⟩. If you have a bug report for this manual page, see ⟨https://www.trace-cmd.org/⟩. This page was obtained from the project's upstream Git repository ⟨https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git⟩ on 2025-08-11. (At that time, the date of the most recent commit that was found in the repository was 2025-06-02.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which isnot part of the original manual page), send a mail to man-pages@man7.orglibtracefs 1.7.0 12/22/2023LIBTRACEFS(3)HTML rendering created 2025-09-06 byMichael Kerrisk, author ofThe Linux Programming Interface. For details of in-depthLinux/UNIX system programming training courses that I teach, lookhere. Hosting byjambit GmbH. | |