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Questions tagged [free]

free is a function to deallocate memory obtained from malloc and other functions in C. Do not use this tag to refer to free software. Asking for software recommendation is off-topic on Stack Overflow. If you have a question about free software, you can ask here: https://softwarerecs.stackexchange.com/

free() is the Standard C (ISO 9899:1989) function declared in <stdlib.h> to deallocate memory allocated by a previous call to malloc, calloc, or realloc. On POSIX (IEEE Std 1003.1) systems, it is also used to free memory obtained from calls to posix_memalign and strdup.

NAME

free - free allocated memory

SYNOPSIS

#include <stdlib.h>

void free(void *ptr);

DESCRIPTION

The free() function frees the memory space pointed to by ptr, which must have been returned by a previous call to malloc(), calloc() or realloc(). Otherwise, or if free(ptr) has already been called before, undefined behavior occurs. If ptr is NULL, no operation is performed.

RETURN VALUE

The free() function returns no value.

Wikipedia

References

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Today, I appeared for an interview and the interviewer asked me this, Tell me the steps how will you design your own free( ) function for deallocate the allocated memory. How can it be more efficient than C's default free() function ?…
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How do I free a pointer returned from a function?

#include #include #include char* f(void) { char *x; x = malloc(sizeof(char) * 4); strcpy(x, "abc"); return(x); } int main(void) { char *a; a = f(); printf("%s", a); free(a); return(0); } Does the…
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Oleg Razgulyaev
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When a program terminates what happens to the memory allocated using malloc that is not free'ed?

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Sangeeth Saravanaraj
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Why is my pointer not null after free?

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Jeegar Patel
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skmiley1
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Free dependency graph of visual studio C# project

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Anto098
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