backtrace(3) BSD Library Functions Manual backtrace(3)

NAME
     bbaacckkttrraaccee, bbaacckkttrraacceessyymmbboollss, bbaacckkttrraacceessyymmbboollssffdd - call stack back-
     trace and display functions

SYNOPSIS
     ##iinncclluuddee <>

     int
     bbaacckkttrraaccee(void** array, int size);

     char**
     bbaacckkttrraacceessyymmbboollss(void* const* array, int size);

     void
     bbaacckkttrraacceessyymmbboollssffdd(void* const* array, int size, int fd);

DESCRIPTION
     These routines provide a mechanism to examine the current thread's call
     stack.

     bbaacckkttrraaccee() writes the function return addresses of the current call
     stack to the array of pointers referenced by array.  At most, size point-
     ers are written.  The number of pointers actually written to array is
     returned.

     bbaacckkttrraacceessyymmbboollss() attempts to transform a call stack obtained by
     bbaacckkttrraaccee() into an array of human-readable strings using ddllaaddddrr().  The
     array of strings returned has size elements.  It is allocated using
     mmaalllloocc() and should be released using ffrreeee().  There is no need to free
     the individual strings in the array.

     bbaacckkttrraacceessyymmbboollssffdd() performs the same operation as
     bbaacckkttrraacceessyymmbboollss(), but the resulting strings are immediately written to
     the file descriptor fd, and are not returned.

EEXXAAMMPPLLEE
         #include 
         #include 
         ...
         void* callstack[128];
         int i, frames = backtrace(callstack, 128);
         char** strs = backtracesymbols(callstack, frames);
         for (i = 0; i < frames; ++i) {
             printf("%s\n", 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