10-15-2005
When to use Malloc?
Hi!
I hope this is the correct forum to post the question even if I'm a newbie...
I am a C-newbie (and really on the edge to be a C-addict
) and have a question.
When should I use malloc?
To state it differently, when should I NOT use malloc?
For instance, if I have an array of chararray/string pointers . Should I allocate space for both the array AND the strings?
Thank you for reading my question.
This really has been bugging me lately...
Tonje
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LEARN ABOUT MOJAVE
backtrace_symbols_fd
backtrace(3) BSD Library Functions Manual backtrace(3)
NAME
backtrace, backtrace_symbols, backtrace_symbols_fd -- call stack backtrace and display functions
SYNOPSIS
#include <execinfo.h>
int
backtrace(void** array, int size);
char**
backtrace_symbols(void* const* array, int size);
void
backtrace_symbols_fd(void* const* array, int size, int fd);
DESCRIPTION
These routines provide a mechanism to examine the current thread's call stack.
backtrace() writes the function return addresses of the current call stack to the array of pointers referenced by array. At most, size
pointers are written. The number of pointers actually written to array is returned.
backtrace_symbols() attempts to transform a call stack obtained by backtrace() into an array of human-readable strings using dladdr(). The
array of strings returned has size elements. It is allocated using malloc() and should be released using free(). There is no need to free
the individual strings in the array.
backtrace_symbols_fd() performs the same operation as backtrace_symbols(), but the resulting strings are immediately written to the file
descriptor fd, and are not returned.
EXAMPLE
#include <execinfo.h>
#include <stdio.h>
...
void* callstack[128];
int i, frames = backtrace(callstack, 128);
char** strs = backtrace_symbols(callstack, frames);
for (i = 0; i < frames; ++i) {
printf("%s
", strs[i]);
}
free(strs);
...
HISTORY
These functions first appeared in Mac OS X 10.5.
SEE ALSO
dladdr(3), malloc(3)
Mac OS X February 15, 2007 Mac OS X