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THR_SET_NAME(2)           FreeBSD System Calls Manual          THR_SET_NAME(2)

NAME
     thr_set_name - set user-visible thread name

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <sys/thr.h>

     int
     thr_set_name(long id, const char *name);

DESCRIPTION
     The thr_set_name() system call sets the user-visible name for the thread
     with the identifier id in the current process to the NUL-terminated
     string name.  The name will be silently truncated to fit into a buffer of
     MAXCOMLEN + 1 bytes.  The thread name can be seen in the output of the
     ps(1) and top(1) commands, in the kernel debuggers and kernel tracing
     facility outputs, and in userland debuggers and program core files, as
     notes.

RETURN VALUES
     If successful, thr_set_name() returns zero; otherwise, -1 is returned,
     and errno is set to indicate the error.

ERRORS
     The thr_set_name() system call may return the following errors:

     [EFAULT]           The memory pointed to by the name argument is not
                        valid.

     [ESRCH]            The thread with the identifier id does not exist in
                        the current process.

SEE ALSO
     ps(1), thr_exit(2), thr_kill(2), thr_kill2(2), thr_new(2), thr_self(2),
     _umtx_op(2), pthread_set_name_np(3), ddb(4), ktr(9)

STANDARDS
     The thr_set_name() system call is non-standard and is used by the 1:1
     Threading Library (libthr, -lthr).

FreeBSD 11.1-RELEASE-p4        December 2, 2016        FreeBSD 11.1-RELEASE-p4
Command Section