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Full Discussion: When to use Malloc?
Top Forums Programming When to use Malloc? Post 86571 by Tonje on Saturday 15th of October 2005 01:17:48 PM
Old 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 Smilie ) 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. Smilie This really has been bugging me lately... Smilie
Tonje
 

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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
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