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ATOI(3P)			    POSIX Programmer's Manual				 ATOI(3P)

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of
       this interface may differ (consult the corresponding Linux  manual  page  for  details  of
       Linux behavior), or the interface may not be implemented on Linux.

       atoi - convert a string to an integer

       #include <stdlib.h>

       int atoi(const char *str);

       The call atoi(str) shall be equivalent to:

	      (int) strtol(str, (char **)NULL, 10)

       except  that  the  handling  of errors may differ. If the value cannot be represented, the
       behavior is undefined.

       The atoi() function shall return the converted value if the value can be represented.

       No errors are defined.

       The following sections are informative.

   Converting an Argument
       The following example checks for proper usage of the program. If there is an argument  and
       the  decimal  conversion  of this argument (obtained using atoi()) is greater than 0, then
       the program has a valid number of minutes to wait for an event.

	      #include <stdlib.h>
	      #include <stdio.h>
	      int minutes_to_event;
	      if (argc < 2 || ((minutes_to_event = atoi (argv[1]))) <= 0) {
		 fprintf(stderr, "Usage: %s minutes\n", argv[0]); exit(1);

       The atoi() function is subsumed by strtol() but is retained because it is used extensively
       in  existing  code.  If	the  number  is not known to be in range, strtol() should be used
       because atoi() is not required to perform any error checking.



       strtol(), the Base Definitions volume of IEEE Std 1003.1-2001, <stdlib.h>

       Portions of this text are reprinted and	reproduced  in	electronic  form  from	IEEE  Std
       1003.1,	2003  Edition,	Standard  for Information Technology -- Portable Operating System
       Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003  by
       the  Institute  of  Electrical  and  Electronics Engineers, Inc and The Open Group. In the
       event of any discrepancy between this version and the original IEEE  and  The  Open  Group
       Standard, the original IEEE and The Open Group Standard is the referee document. The orig-
       inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group			       2003					 ATOI(3P)
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