strtoumax() — Convert character string to uintmax_t integer type

Standards

Format

#define _ISOC99_SOURCE
#include <inttypes.h>

uintmax_t strtoumax(const char * __restrict__ nptr, 
                    char ** __restrict__ endptr, int base);

General description

The strtoumax() function converts the string nptr to an uintmax_t integer type. Valid input values for base are 0 and in the range 2-36. The strtoumax() function is equivalent to strtoul() and strtoull(). The only difference being that the return value is of type uintmax_t. See strtoull for more information.

Returned value

If successful, strtoumax() returns the converted uintmax_t value, represented in the string.

If unsuccessful, strtoumax() returns 0 if no conversion could be performed. If the correct value is outside the range of representable values, strtoumax() returns UINTMAX_MAX. If the value of base is not supported, strtoumax() returns 0.

If unsuccessful strtoumax() sets errno to one of the following values:

Error Code

Description

EINVAL

The value of base is not supported.

ERANGE

The conversion caused an overflow.

Example

#define _ISOC99_SOURCE
#include <inttypes.h>
#include <stdlib.h>
#include <stdio.h>

      int main(void)                                             
       {                                                     
          uintmax_t j;                                       
          int base = 10;                                     
          char *nptr, *endptr;                               
          nptr = "20690239864abc";                           
          printf("string = %s\n", nptr);                     
          j = strtoumax(nptr, &endptr, base);                
          printf("strtoumax = %ju (base %d)\n", j, base);
          printf("Stopped scan at %s\n\n", endptr);       
       }                                                     

Output

string = 20690239864abc             
strtoumax = 20690239864 (base 10)
Stopped scan at abc              

Related information

• inttypes.h
• strtoimax()
• strtol()
• strtoul()
• strtoll()
• strtoull()
• wcstoimax()
• wcstoumax()