libc/stdlib/getenv.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2009  Tomas 'ZeXx86' Jedrzejek (zexx86@gmail.com)
   4  *
   5  *  This program is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19
  20 char *getenv (const char *name)
  21 {
  22         char *ret = (char *) 0;
  23
  24         asm volatile (
  25                 "movl $42, %%eax;"
  26                 "movl %1, %%ebx;"
  27                 "int $0x80;"
  28                 "movl %%eax, %0;" : "=g" (ret) : "b" (name): "%eax", "memory");
  29
  30         return ret;
  31 }