kstat_write(3kstat)

1kstat_read(3KSTAT)    Kernel Statistics Library Functions   kstat_read(3KSTAT)
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NAME

6       kstat_read, kstat_write - read or write kstat data
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SYNOPSIS

9       cc [ flag... ] file... -lkstat [ library... ]
10       #include <kstat.h>
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12       kid_t kstat_read(kstat_ctl_t *kc, kstat_t *ksp, void *buf);
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15       kid_t kstat_write(kstat_ctl_t *kc, kstat_t *ksp, void *buf);
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DESCRIPTION

19       The  kstat_read()  function  gets  data  from  the kernel for the kstat
20       pointed to by ksp. The ksp->ks_data field  is  automatically  allocated
21       (or  reallocated)  to  be  large  enough  to  hold all of the data. The
22       ksp->ks_ndata  field  is  set   to   the   number   of   data   fields,
23       ksp->ks_data_size   is   set  to  the  total  size  of  the  data,  and
24       ksp->ks_snaptime is set to the high-resolution time at which  the  data
25       snapshot  was  taken.  If  buf  is   non-null,  the data is copied from
26       ksp->ks_data to buf.
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29       The kstat_write() function writes data from buf, or  from  ksp->ks_data
30       if  buf  is  NULL,  to the corresponding kstat in the kernel.  Only the
31       superuser can use kstat_write().
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RETURN VALUES

34       Upon successful completion, kstat_read() and kstat_write()  return  the
35       current  kstat chain ID (KCID). Otherwise, they return −1 and set errno
36       to indicate the error.
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ERRORS

39       The kstat_read() and kstat_write() functions will fail if:
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41       EACCES       An attempt was made to write to a non-writable kstat.
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44       EAGAIN       The kstat was temporarily unavailable for reading or writ‐
45                    ing.
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48       EINVAL       An attempt was made to write data to a kstat, but the num‐
49                    ber of elements or the data size does not match.
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52       ENOMEM       Insufficient storage space is available.
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55       ENXIO        The given kstat could not be located for reading or  writ‐
56                    ing.
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59       EOVERFLOW    The data for the given kstat was too large to be stored in
60                    the structure.
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63       EPERM        An  attempt  was  made  to   write   to   a   kstat,   but
64                    {PRIV_SYS_CONFIG} was not asserted in the effective privi‐
65                    lege set.
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FILES

69       /dev/kstat    kernel statistics driver
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ATTRIBUTES

73       See attributes(5) for descriptions of the following attributes:
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78       ┌─────────────────────────────┬─────────────────────────────┐
79       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
80       ├─────────────────────────────┼─────────────────────────────┤
81       │Interface Stability          │Stable                       │
82       ├─────────────────────────────┼─────────────────────────────┤
83       │MT-Level                     │Unsafe                       │
84       └─────────────────────────────┴─────────────────────────────┘
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