| #include <stdlib.h> | |
| #include <ctype.h> | |
| long atol(const char *s) | |
| { | |
| long n=0; | |
| int neg=0; | |
| while (isspace(*s)) s++; | |
| switch (*s) { | |
| case '-': neg=1; | |
| case '+': s++; | |
| } | |
| /* Compute n as a negative number to avoid overflow on LONG_MIN */ | |
| while (isdigit(*s)) | |
| n = 10*n - (*s++ - '0'); | |
| return neg ? n : -n; | |
| } |