_aaaa_tttt_ffff_oooo_rrrr_kkkk______cccc_hhhh_iiii_llll_dddd adds the function _f_u_n_c to the end of a list of functions to
be called without arguments on entry of a child process created by
_ffff_oooo_rrrr_kkkk(2). _aaaa_tttt_ffff_oooo_rrrr_kkkk______cccc_hhhh_iiii_llll_dddd______pppp_rrrr_eeee_pppp_eeee_nnnn_dddd performs the same task, but it adds the
function at the beginning of the list. At most 32 functions may be
registered by _aaaa_tttt_ffff_oooo_rrrr_kkkk______cccc_hhhh_iiii_llll_dddd or _aaaa_tttt_ffff_oooo_rrrr_kkkk______cccc_hhhh_iiii_llll_dddd______pppp_rrrr_eeee_pppp_eeee_nnnn_dddd. The functions will
be called in list order.
_aaaa_tttt_ffff_oooo_rrrr_kkkk______pppp_aaaa_rrrr_eeee_nnnn_tttt adds the function _f_u_n_c to a list of functions to be called
with two integer arguments after calling _ffff_oooo_rrrr_kkkk(2). At most 32 functions
may be registered by _aaaa_tttt_ffff_oooo_rrrr_kkkk______pppp_aaaa_rrrr_eeee_nnnn_tttt; the functions will be called in the
same order as their registration.
_aaaa_tttt_ffff_oooo_rrrr_kkkk______pppp_rrrr_eeee adds the function _f_u_n_c to a list of functions to be called
without arguments just preceeding a call to _ffff_oooo_rrrr_kkkk(2). At most 32
functions may be registered by _aaaa_tttt_ffff_oooo_rrrr_kkkk______pppp_rrrr_eeee; the functions will be called
in the reverse order as their registration.
_aaaa_tttt_ffff_oooo_rrrr_kkkk______cccc_hhhh_iiii_llll_dddd, _aaaa_tttt_ffff_oooo_rrrr_kkkk______cccc_hhhh_iiii_llll_dddd______pppp_rrrr_eeee_pppp_eeee_nnnn_dddd, _aaaa_tttt_ffff_oooo_rrrr_kkkk______pppp_aaaa_rrrr_eeee_nnnn_tttt, and _aaaa_tttt_ffff_oooo_rrrr_kkkk______pppp_rrrr_eeee all
return 0 if the registration succeeds. Otherwise, a value of -1 is
returned and _e_r_r_n_o is set to indicate the error.