strtol, atol, atoi

Purpose

     Converts a string to an integer.

Library

     Standard C Library (libc.a)

Syntax

     long strtol (str, ptr, base)              long atol (str)
     char *str, **ptr;                         char *str;
     int base;
                                               int atoi (str)
                                               char *str;
     Description

     The strtol subroutine returns  a long integer whose value
     is represented by the character string str.  strtol scans
     the string up to the first character that is inconsistent
     with  the  base.    Leading  white-space  characters  are
     ignored.

     Warning:  Overflow conditions are ignored.

     If the value of ptr is not (char **) NULL, then a pointer
     to the  character that terminated  the scan is  stored in
     *ptr.  If  an integer  cannot be formed,  *ptr is  set to
     str, and 0 is returned.

     If the  base parameter is  positive and not  greater than
     36, then it is used as the base for conversion.  After an
     optional leading sign, leading  zeroes are ignored.  "0x"
     or "0X" is ignored if base is 16.

     If the  base parameter  is 0,  the string  determines the
     base.  Thus, after an optional  leading sign, a leading 0
     indicates octal  conversion, and  a leading "0x"  or "0X"
     indicates hexadecimal conversion.  The  default is to use
     decimal conversion.

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

     The atol  (str) subroutine  call is equivalent  to strtol
     (str, (char **) NULL, 10).

     The  atoi (str)  subroutine call  is equivalent  to (int)
     strtol (str, (char **) NULL, 10).

     The  atoi  and  atol  subroutines do  not  actually  call
     strtol.

     The strtol,  atol, and  atoi subroutines  perform conver-
     sions to integers.  See "strtod, atof" for information on
     conversions to floating-point numbers.

     Related Information

     In this book:  "strtod, atof" and "scanf, fscanf, sscanf,
     NLscanf, NLfscanf, NLsscanf."