strtol(3C)          (C Programming Language Utilities)           strtol(3C)


   NAME
         strtol, strtoul, atol, atoi - convert string to integer

   SYNOPSIS
         #include <stdlib.h>

         long strtol (const char *str, char **ptr, int base);

         unsigned long strtoul (const char *str, char **ptr, int base);

         long atol (const char *str);

         int atoi (const char *str);

   DESCRIPTION
         strtol returns as a long integer the value represented by the
         character string pointed to by str.  The string is scanned up to the
         first character inconsistent with the base.  Leading ``white-space''
         characters [as defined by isspace in ctype(3C)] are ignored.

         If the value of ptr is not (char **)NULL, a pointer to the character
         terminating the scan is returned in the location pointed to by ptr.
         If no integer can be formed, that location is set to str, and zero is
         returned.

         If base is positive (and not greater than 36), it is used as the base
         for conversion.  After an optional leading sign, leading zeros are
         ignored, and ``0x'' or ``0X'' is ignored if base is 16.

         If base is zero, the string itself determines the base as follows:
         After an optional leading sign a leading zero indicates octal
         conversion, and a leading ``0x'' or ``0X'' hexadecimal conversion.
         Otherwise, decimal conversion is used.

         Truncation from long to int can, of course, take place upon
         assignment or by an explicit cast.

         If the value represented by str would cause overflow, LONGMAX or
         LONGMIN is returned (according to the sign of the value), and errno
         is set to the value, ERANGE.

         strtoul is similar to strtol except that strtoul returns as an
         unsigned long integer the value represented by str.  If the value
         represented by str would cause overflow, ULONGMAX is returned, and
         errno is set to the value, ERANGE.

         Except for behavior on error, atol(str) is equivalent to:
         strtol(str, (char **)NULL, 10).





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   strtol(3C)          (C Programming Language Utilities)           strtol(3C)


         Except for behavior on error, atoi(str) is equivalent to:  (int)
         strtol(str, (char **)NULL, 10).

   DIAGNOSTICS
         If strtol is given a base greater than 36, it returns 0 and sets
         errno to EINVAL.

   SEE ALSO
         ctype(3C), scanf(3S), strtod(3C).

   NOTES
         strtol no longer accepts values greater than LONGMAX as valid input.
         Use strtoul instead.








































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