atol, atoll - convert a string to a long integer
long atol(const char *nptr);
long long atoll(const char *nptr);
[CX] The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1-2017 defers to the ISO C standard.
Except as noted below, the call atol(nptr) shall be equivalent to:strtol(nptr, (char **)NULL, 10)
Except as noted below, the call to atoll(nptr) shall be equivalent to:strtoll(nptr, (char **)NULL, 10)
The handling of errors may differ. If the value cannot be represented, the behavior is undefined.
These functions shall return the converted value if the value can be represented.
No errors are defined.
If the number is not known to be in range, strtol() or strtoll() should be used because atol() and atoll() are not required to perform any error checking.
First released in Issue 1. Derived from Issue 1 of the SVID.
The atoll() function is added for alignment with the ISO/IEC 9899:1999 standard.
SD5-XSH-ERN-61 is applied, correcting the DESCRIPTION of atoll().
POSIX.1-2008, Technical Corrigendum 2, XSH/TC2-2008/0046  is applied.
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