ssttrrccssppnn() -- String Function (libc)

Return length a string excludes characters in another
#iinncclluuddee <ssttrriinngg.hh>
uunnssiiggnneedd iinntt ssttrrccssppnn(_s_t_r_i_n_g_1, _s_t_r_i_n_g_2)
cchhaarr *_s_t_r_i_n_g_1, *_s_t_r_i_n_g_2;

ssttrrccssppnn() compares  _s_t_r_i_n_g_1 with  _s_t_r_i_n_g_2. It  then returns the  length, in
characters, for which _s_t_r_i_n_g_1 consists of characters _n_o_t found in _s_t_r_i_n_g_2.

_S_e_e _A_l_s_o
lliibbcc, ssttrriinngg.hh
ANSI Standard, section 7.11.5.3
POSIX Standard, section 8.1
