Updated: April 19, 2023 |
Convert a string into a long integer
#include <stdlib.h> long int strtol( const char * ptr, char ** endptr, int base ); long long strtoll( const char * ptr, char ** endptr, int base );
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
The strtol() function converts the string pointed to by ptr to an object of type long int; strtoll() converts the string pointed to by ptr to an object of type long long.
These functions recognize strings that contain the following:
The conversion ends at the first unrecognized character. If endptr isn't NULL, a pointer to the unrecognized character is stored in the object endptr points to.
The converted value.
If the correct value causes an overflow, the returned value is LONG_MAX, LLONG_MAX, LONG_MIN, or LLONG_MIN, depending on the function and the sign, and errno is set to ERANGE. If base is out of range, or no conversion can be made, the function returns zero and sets errno to EINVAL.
#include <stdlib.h> int main( void ) { long int v; v = strtol( "12345678", NULL, 10 ); return EXIT_SUCCESS; }
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | Yes |
Signal handler | Yes |
Thread | Yes |