dereference


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dereference

(programming)
To access the thing to which a pointer points, i.e. to follow the pointer. E.g. in C, the declarations

int i; int *p = &i;

declare i as an integer and p as a pointer to integer. p is initialised to point at i ("&i" is the address of i - the inverse of "*"). The expression *p dereferences p to yield i as an lvalue, i.e. something which can appear either on the left of an assignment or anywhere an integer expression is valid. Thus

*p = 17;

would set i to 17. *p++ is not the same as i++ however since it is parsed as *(p++), i.e. increment p (which would be an invalid thing to do if it was pointing to a single int, as in this example) then dereference p's old value.

The C operator "->" also dereferences its left hand argument which is assumed to point to a structure or union of which the right hand argument is a member.

At first sight the word "dereference" might be thought to mean "to cause to stop referring" but its meaning is well established in jargon.

dereference

To go to an address before performing the operation. For example, in C programming, a dereferenced variable is a pointer to the variable, not the variable itself. The expression int Num; declares an integer variable named "Num." The expression *pNum = &Num; places the address of the variable Num (not its contents) into the pointer. The ampersand is the "address of" operator.

Another example is found in the tar archiving program. The dereference switch causes files referenced by symbolic links to be archived rather than the symbolic link itself. The term always refers to "following the link" in order to obtain the intended resource. See symbolic link.
References in periodicals archive ?
Since semantically, dereference (*) and address (&) are effectively inverse operations (13) (&,r' [equivalent to] *&r' [equivalent to] r'), in the above case r' will be unchanged.
Whenever TPA-TBAA or ITPA-TBAA encounter a pointer dereference, they invoke TFM-TBAA to get the set of locations referenced by the pointer dereference.
The ensuing dereference cannot preserve the type of
Finally, it returns from the memory fault, which causes the dereference to restart.
An access path is the 1-value of an expression that is constructed from variables, pointer dereference operators, and structure field selection operators.
DEREFERENCE [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII]
Thus, the code in Figure 3 will dereference an integer.
we need to dereference p's sptr and call the function whose address is stored in the data member _g, which is C::g in our example.
The service is designed to find the most common and critical issues in Java code bases, including resource leaks, race conditions, concurrency issues, control flow issues, null pointer dereferences, issues detected by the open source FindBugs tool, copy and paste errors, and many other software defects resulting in incorrect or unpredictable program behavior.
tablecheck](v) policy, Icefex focuses on the targeted address dependencies and avoids the explosion caused by full symbolic pointer dereferences [21].
1) It employs novel static analysis techniques, combined with model checking and constraint solving to search for common predefined software defects such as buffer overflows or null-pointer dereferences with very low rates of false positives.
After locating the URI of a resource, the LOD retrieval process dereferences that URI at the DBpedia server to get the respective resource RDF description.