function strtol in C out of range… or not
Pregunta
I try to read a number from a string with strtol() and it returns the LONG_MAX number which is supposed to return when the number is out of range, but my number is not that big
main(){
char linea[30]={"110111010111111000000000"};
long num=strtol(linea,NULL,0);
printf("%s\n%X",linea,num);
}
Actual Result:
110111010111111000000000
7FFFFFFF
Needed Result:
110111010111111000000000
DD7C00
Solución
According to the man page for strtol, the '0' argument you've given means 'use you best judgement', which in this case is decimal. If you want it to convert a binary number, as the 'Needed result' you've specified suggests, don't use '0', use '2'.
Otros consejos
probably because you pass in base 0
try:
int main(){
char linea[30] = {"110111010111111000000000"};
long num = strtol(linea, NULL, 10);
printf("%s\n%X", linea, num);
}
EDIT
Apparently base 0 is a special value for the strtol
function:
If the value of base is 0, the expected form of the subject sequence is that of a decimal constant, octal constant, or hexadecimal constant, any of which may be preceded by a '+' or '-' sign.
So I guess you can use 0, sorry for doubting you.