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/ IRIX Base Documentation 2002 November / SGI IRIX Base Documentation 2002 November.iso / usr / share / catman / p_man / cat2 / standard / semctl.z / semctl
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Text File  |  2002-10-03  |  11.7 KB  |  199 lines
  1.  
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  4. sssseeeemmmmccccttttllll((((2222))))                                                            sssseeeemmmmccccttttllll((((2222))))
  5.  
  6.  
  7.  
  8. NNNNAAAAMMMMEEEE
  9.      _ssss_eeee_mmmm_cccc_tttt_llll - semaphore control operations
  10.  
  11. SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
  12.      _####_iiii_nnnn_cccc_llll_uuuu_dddd_eeee _<<<<_ssss_yyyy_ssss_////_tttt_yyyy_pppp_eeee_ssss_...._hhhh_>>>>
  13.      _####_iiii_nnnn_cccc_llll_uuuu_dddd_eeee _<<<<_ssss_yyyy_ssss_////_iiii_pppp_cccc_...._hhhh_>>>>
  14.      _####_iiii_nnnn_cccc_llll_uuuu_dddd_eeee _<<<<_ssss_yyyy_ssss_////_ssss_eeee_mmmm_...._hhhh_>>>>
  15.  
  16.      _uuuu_nnnn_iiii_oooo_nnnn _ssss_eeee_mmmm_uuuu_nnnn _{{{{
  17.           _iiii_nnnn_tttt _vvvv_aaaa_llll_;;;;
  18.           _ssss_tttt_rrrr_uuuu_cccc_tttt _ssss_eeee_mmmm_iiii_dddd______dddd_ssss _****_bbbb_uuuu_ffff_;;;;
  19.           _uuuu_ssss_hhhh_oooo_rrrr_tttt _****_aaaa_rrrr_rrrr_aaaa_yyyy_;;;;
  20.      _}}}}_;;;;
  21.  
  22.      _iiii_nnnn_tttt _ssss_eeee_mmmm_cccc_tttt_llll_((((_iiii_nnnn_tttt _ssss_eeee_mmmm_iiii_dddd_,,,, _iiii_nnnn_tttt _ssss_eeee_mmmm_nnnn_uuuu_mmmm_,,,, _iiii_nnnn_tttt _cccc_mmmm_dddd_,,,, _...._...._.... _////_**** _uuuu_nnnn_iiii_oooo_nnnn _ssss_eeee_mmmm_uuuu_nnnn _aaaa_rrrr_gggg _****_////_))))_;;;;
  23.  
  24. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  25.      _ssss_eeee_mmmm_cccc_tttt_llll provides a variety of semaphore control operations as specified by
  26.      _c_m_d.
  27.  
  28.      The following _c_m_ds are executed with respect to the semaphore specified
  29.      by _s_e_m_i_d and _s_e_m_n_u_m:
  30.  
  31.           _GGGG_EEEE_TTTT_VVVV_AAAA_LLLL     Return the value of _ssss_eeee_mmmm_vvvv_aaaa_llll [see _iiii_nnnn_tttt_rrrr_oooo(2)].  {READ}
  32.  
  33.           _SSSS_EEEE_TTTT_VVVV_AAAA_LLLL     Set the value of _ssss_eeee_mmmm_vvvv_aaaa_llll to _a_r_g._vvvv_aaaa_llll.  {ALTER}.  When this
  34.                      command is successfully executed, the _ssss_eeee_mmmm_aaaa_dddd_jjjj value
  35.                      corresponding to the specified semaphore in all processes
  36.                      is cleared.
  37.  
  38.           _GGGG_EEEE_TTTT_PPPP_IIII_DDDD     Return the value of _((((_iiii_nnnn_tttt_)))) _ssss_eeee_mmmm_pppp_iiii_dddd.  {READ}
  39.  
  40.           _GGGG_EEEE_TTTT_NNNN_CCCC_NNNN_TTTT    Return the value of _ssss_eeee_mmmm_nnnn_cccc_nnnn_tttt.  {READ}
  41.  
  42.           _GGGG_EEEE_TTTT_ZZZZ_CCCC_NNNN_TTTT    Return the value of _ssss_eeee_mmmm_zzzz_cccc_nnnn_tttt.  {READ}
  43.  
  44.      The following _c_m_ds return and set, respectively, every _ssss_eeee_mmmm_vvvv_aaaa_llll in the set
  45.      of semaphores.
  46.  
  47.           _GGGG_EEEE_TTTT_AAAA_LLLL_LLLL     Place _ssss_eeee_mmmm_vvvv_aaaa_lllls into array pointed to by _a_r_g._aaaa_rrrr_rrrr_aaaa_yyyy.  {READ}
  48.  
  49.           _SSSS_EEEE_TTTT_AAAA_LLLL_LLLL     Set _ssss_eeee_mmmm_vvvv_aaaa_lllls according to the array pointed to by
  50.                      _a_r_g._aaaa_rrrr_rrrr_aaaa_yyyy.  {ALTER}.  When this cmd is successfully
  51.                      executed, the _ssss_eeee_mmmm_aaaa_dddd_jjjj values corresponding to each
  52.                      specified semaphore in all processes are cleared.
  53.  
  54.      The following _c_m_ds are also available:
  55.  
  56.           _IIII_PPPP_CCCC______SSSS_TTTT_AAAA_TTTT   Place the current value of each member of the data
  57.                      structure associated with _s_e_m_i_d into the structure
  58.                      pointed to by _a_r_g._bbbb_uuuu_ffff.  The contents of this structure
  59.                      are defined in _iiii_nnnn_tttt_rrrr_oooo(2).  {READ}
  60.  
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  62.  
  63.                                                                         PPPPaaaaggggeeee 1111
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  70. sssseeeemmmmccccttttllll((((2222))))                                                            sssseeeemmmmccccttttllll((((2222))))
  71.  
  72.  
  73.  
  74.           _IIII_PPPP_CCCC______SSSS_EEEE_TTTT    Set the value of the following members of the data
  75.                      structure associated with _s_e_m_i_d to the corresponding
  76.                      value found in the structure pointed to by _a_r_g._bbbb_uuuu_ffff:
  77.  
  78.                          _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._uuuu_iiii_dddd
  79.                          _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._gggg_iiii_dddd
  80.                          _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._mmmm_oooo_dddd_eeee _////_**** _oooo_nnnn_llll_yyyy _aaaa_cccc_cccc_eeee_ssss_ssss _pppp_eeee_rrrr_mmmm_iiii_ssss_ssss_iiii_oooo_nnnn _bbbb_iiii_tttt_ssss _****_////
  81.  
  82.                      This command can be executed only by a process that has
  83.                      an effective user ID equal to the value of _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._cccc_uuuu_iiii_dddd
  84.                      or _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._uuuu_iiii_dddd in the data structure associated with
  85.                      _s_e_m_i_d or to a process that has the _ssss_uuuu_pppp_eeee_rrrr_----_uuuu_ssss_eeee_rrrr privilege.
  86.  
  87.           _IIII_PPPP_CCCC______RRRR_MMMM_IIII_DDDD   Remove the semaphore identifier specified by _s_e_m_i_d from
  88.                      the system and destroy the set of semaphores and data
  89.                      structure associated with it.  This command can be
  90.                      executed only by a process that has an effective user ID
  91.                      equal to the value of _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._cccc_uuuu_iiii_dddd or _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._uuuu_iiii_dddd in
  92.                      the data structure associated with _s_e_m_i_d or to a process
  93.                      that has the _ssss_uuuu_pppp_eeee_rrrr_----_uuuu_ssss_eeee_rrrr privilege.
  94.  
  95.      _ssss_eeee_mmmm_cccc_tttt_llll fails if one or more of the following are true:
  96.  
  97.      _EEEE_AAAA_CCCC_CCCC_EEEE_SSSS         Operation permission is denied to the calling process [see
  98.                     _iiii_nnnn_tttt_rrrr_oooo(2)].
  99.  
  100.      _EEEE_IIII_NNNN_VVVV_AAAA_LLLL         _s_e_m_i_d is not a valid semaphore identifier.
  101.  
  102.      _EEEE_IIII_NNNN_VVVV_AAAA_LLLL         _s_e_m_n_u_m is less than 0 or greater than _ssss_eeee_mmmm______nnnn_ssss_eeee_mmmm_ssss.
  103.  
  104.      _EEEE_IIII_NNNN_VVVV_AAAA_LLLL         _c_m_d is not a valid command.
  105.  
  106.      _EEEE_IIII_NNNN_VVVV_AAAA_LLLL         _c_m_d is _IIII_PPPP_CCCC______SSSS_EEEE_TTTT and _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._uuuu_iiii_dddd or _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._gggg_iiii_dddd is not
  107.                     valid.
  108.  
  109.      _EEEE_OOOO_VVVV_EEEE_RRRR_FFFF_LLLL_OOOO_WWWW      _c_m_d is _IIII_PPPP_CCCC______SSSS_TTTT_AAAA_TTTT and _u_i_d or _g_i_d is too large to be stored
  110.                     in the structure pointed to by _a_r_g._b_u_f.
  111.  
  112.      _EEEE_RRRR_AAAA_NNNN_GGGG_EEEE         _c_m_d is _SSSS_EEEE_TTTT_VVVV_AAAA_LLLL or _SSSS_EEEE_TTTT_AAAA_LLLL_LLLL and the value to which _ssss_eeee_mmmm_vvvv_aaaa_llll is
  113.                     to be set is greater than the system imposed maximum.
  114.  
  115.      _EEEE_PPPP_EEEE_RRRR_MMMM          _c_m_d is equal to _IIII_PPPP_CCCC______RRRR_MMMM_IIII_DDDD or _IIII_PPPP_CCCC______SSSS_EEEE_TTTT and the effective user
  116.                     ID of the calling process is not equal to the value of
  117.                     _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._cccc_uuuu_iiii_dddd or _ssss_eeee_mmmm______pppp_eeee_rrrr_mmmm_...._uuuu_iiii_dddd in the data structure
  118.                     associated with _s_e_m_i_d and the calling process does not
  119.                     have _ssss_uuuu_pppp_eeee_rrrr_----_uuuu_ssss_eeee_rrrr privilege.
  120.  
  121.      _EEEE_FFFF_AAAA_UUUU_LLLL_TTTT         _a_r_g_...._bbbb_uuuu_ffff points to an illegal address.
  122.  
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  129.                                                                         PPPPaaaaggggeeee 2222
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  135.  
  136. sssseeeemmmmccccttttllll((((2222))))                                                            sssseeeemmmmccccttttllll((((2222))))
  137.  
  138.  
  139.  
  140. SEE ALSO
  141.      _iiii_nnnn_tttt_rrrr_oooo(2), _ssss_eeee_mmmm_gggg_eeee_tttt(2), _ssss_eeee_mmmm_oooo_pppp(2).
  142.  
  143. DDDDIIIIAAAAGGGGNNNNOOOOSSSSTTTTIIIICCCCSSSS
  144.      Upon successful completion, the value returned depends on _c_m_d as follows:
  145.           _GGGG_EEEE_TTTT_VVVV_AAAA_LLLL    the value of _ssss_eeee_mmmm_vvvv_aaaa_llll
  146.           _GGGG_EEEE_TTTT_PPPP_IIII_DDDD    the value of _((((_iiii_nnnn_tttt_)))) _ssss_eeee_mmmm_pppp_iiii_dddd
  147.           _GGGG_EEEE_TTTT_NNNN_CCCC_NNNN_TTTT   the value of _ssss_eeee_mmmm_nnnn_cccc_nnnn_tttt
  148.           _GGGG_EEEE_TTTT_ZZZZ_CCCC_NNNN_TTTT   the value of _ssss_eeee_mmmm_zzzz_cccc_nnnn_tttt
  149.           all others
  150.                     a value of 0
  151.      Otherwise, a value of -1 is returned and _eeee_rrrr_rrrr_nnnn_oooo is set to indicate the
  152.      error.
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  195.                                                                         PPPPaaaaggggeeee 3333
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