1 #ifndef lint 2 static char sccsid[] = "@(#)atoi.c 5.1 (Berkeley) 06/05/85"; 3 #endif not lint 4 5 atoi(p) 6 register char *p; 7 { 8 register int n; 9 register int f; 10 11 n = 0; 12 f = 0; 13 for(;;p++) { 14 switch(*p) { 15 case ' ': 16 case '\t': 17 continue; 18 case '-': 19 f++; 20 case '+': 21 p++; 22 } 23 break; 24 } 25 while(*p >= '0' && *p <= '9') 26 n = n*10 + *p++ - '0'; 27 return(f? -n: n); 28 } 29