atoi, atol, atoll, atoq - convert a string to an integer.
#include <stdlib.h>
int atoi(const char *nptr);
long atol(const char *nptr);
long long atoll(const char *nptr);
long long atoq(const char *nptr);
The atoi() function converts the initial portion of the string pointed
to by nptr to int. The behaviour is the same as
strtol(nptr, (char **)NULL, 10);
except that atoi() does not detect errors.
The atol() and atoll() functions behave the same as atoi(), except that
they convert the initial portion of the string to their return type of
long or long long. atoq() is an obsolete name for atoll().
The converted value.
SVID 3, POSIX.1, BSD 4.3, ISO/IEC 9899. ISO/IEC 9899:1990 (C89) and
POSIX.1 (1996 edition) include the functions atoi() and atol() only;
C99 adds the function atoll().
The non-standard atoq() function is not present in libc 4.6.27 or glibc
2, but is present in libc5 and libc 4.7 (though only as an inline function
in <stdlib.h> until libc 5.4.44). The atoll() function is present
in glibc 2 since version 2.0.2, but not in libc4 or libc5.
atof(3), strtod(3), strtol(3), strtoul(3)
GNU 2000-12-17 ATOI(3)
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