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    The following form allows you to view linux man pages.

    Command:

    getcpu

    
    
    
    

    SYNOPSIS

           #include <linux/getcpu.h>
    
           int getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache);
    
           Note: There is no glibc wrapper for this system call; see NOTES.
    
    
    

    DESCRIPTION

           The getcpu() system call identifies the processor and node on which the
           calling thread or process is currently running and writes them into the
           integers pointed to by the cpu and node arguments.  The processor is  a
           unique  small  integer  identifying  a CPU.  The node is a unique small
           identifier identifying a NUMA node.  When either cpu or  node  is  NULL
           nothing is written to the respective pointer.
    
           The  third  argument to this system call is nowadays unused, and should
           be specified as NULL unless portability to Linux 2.6.23 or  earlier  is
           required (see NOTES).
    
           The  information  placed in cpu is guaranteed to be current only at the
           time of the  call:  unless  the  CPU  affinity  has  been  fixed  using
           sched_setaffinity(2),  the  kernel  might  change  the CPU at any time.
           (Normally this does not happen because the scheduler tries to  minimize
           movements  between  CPUs  to keep caches hot, but it is possible.)  The
           caller must allow for the possibility that the information returned  in
           cpu and node is no longer current by the time the call returns.
    
    
    

    RETURN VALUE

           On  success, 0 is returned.  On error, -1 is returned, and errno is set
           appropriately.
    
    
    

    ERRORS

           EFAULT Arguments point outside the calling process's address space.
    
    
    

    VERSIONS

           getcpu() was added in kernel 2.6.19 for x86_64 and i386.
    
    
    

    CONFORMING TO

           getcpu() is Linux-specific.
    
    
    

    NOTES

           Linux makes a best effort to make this  call  as  fast  possible.   The
           intention  of  getcpu() is to allow programs to make optimizations with
           per-CPU data or for NUMA optimization.
    
           Glibc does not provide a wrapper for this system call;  call  it  using
           syscall(2); or use sched_getcpu(3) instead.
    
           The  tcache argument is unused since Linux 2.6.24.  In earlier kernels,
           if this argument was non-NULL, then it specified a pointer to a caller-
           allocated  buffer  in  thread-local  storage that was used to provide a
    
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