They are pointers. This is sure. But there is some mistakes in the code I gave before. The assignment should use * before the pointers. I am sorry for carelessness when posted. But when checking with 'while ( *( tr->root->is_done ) )', the same segfault happen. And corresponding pinter address still be 'out of bounds". In my code, such statements exist.
This is a package coded by a previous member. He habits to use such structure for varialbes which control execution. A large package means that it is not easy to change all the strutures of this kind.
What's more, I think this is really a topic worth discusssion.
Quote:
Originally Posted by otheus
"out of bounds" means "invalid memory address". You avoid it by properly mallocing memory before using it.
I hate to say this, but you seem very confused about pointers. I think you need to read a very concise summary on C pointers.
In the code you provide, you are trying to assign values to the address...
Code:
node->des = 0;
You should instead be doing:
Code:
*(node->des) = 0;
This correction is good. I losed stars when posted.
And your loop should be:
Code:
while ( *( tr->root->is_done ) ) {
...
}
At this situation, segfaults still happen
Also, root itself is a pointer. So you first need to allocate it:
Hi,
I am trying to set up a cron job for every Friday at 6:00 p.m. and got an error:
"/var/tmp/aaaa29638" 1 line, 73 characters
00 18 00 0 5 /app/test/backup.ksh
crontab: error on previous line; number out of bounds.
Any ideas?
Thanks! (1 Reply)
Hello, sorry if this has been posted before but i was wondering if there is a way to run a program until a segmentation fault is found.
Currently i'm using a simple shell script which runs my program 100 times, sleeps 1 second because srand(time(0)) is dependent on seconds. Is there a possible... (1 Reply)
We have a Solaris 8 server which users login to via VNC to get a desktop. On that desktop these users use Netscape Communicator 4.9 to access a very important mail account. Unfortunately Netscape has started segfaulting regularly.
Does anyone have any ideas how I can try to find out what point... (1 Reply)
Hello everyone,
I'm writing a program using the id3lib unfortunately I've encountered with memory issue that cause segmentation fault. I tried to rerun and analyze the program with valgrind but it doesn't point me anywhere. I really stuck on this one.
Valgrind output:
==14716== Invalid read of... (2 Replies)
I have a program that allows users to specify the debug log file location and name.
I have tried using the access() and stat() but they both segfault if the drive say (d:\) is invalid. Both seem to be fine if the drive exists.
Could someone please point me in the direction to a function that... (1 Reply)
hello all,
my question is not about How code can be rewritten, i just wanna know even though i am not using read only memory of C (i have declared str) why this function gives me segfault :wall:and the other code executes comfortably though both code uses same pointer arithmetic.
... (4 Replies)
Hi,
I've been trying to filter a file which has several repetitions of lines which looks as follows:
('hello
My name is
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blabla
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Another project, another bump in the road and another chance to learn. I've been trying to open gzipped files and parse data from them and hit a snag. I have data in gzips with a place followed by an ip or ip range sort of like this:
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What exactly is the -Warray-bounds option to the GCC compiler supposed to warn about?
the man page states:
~ g++ --version
g++ (GCC) 7.3.1 20180130 (Red Hat 7.3.1-2)
Copyright (C) 2017 Free Software Foundation, Inc.Thank you. (14 Replies)
Discussion started by: milhan
14 Replies
LEARN ABOUT LINUX
malloc_get_state
MALLOC_GET_STATE(3) Linux Programmer's Manual MALLOC_GET_STATE(3)NAME
malloc_get_state, malloc_set_state - record and restore state of malloc implementation
SYNOPSIS
#include <malloc.h>
void* malloc_get_state(void);
int malloc_set_state(void *state);
DESCRIPTION
The malloc_get_state() function records the current state of all malloc(3) internal bookkeeping variables (but not the actual contents of
the heap or the state of malloc_hook(3) functions pointers). The state is recorded in a system-dependent opaque data structure dynamically
allocated via malloc(3), and a pointer to that data structure is returned as the function result. (It is the caller's responsibility to
free(3) this memory.)
The malloc_set_state() function restores the state of all malloc(3) internal bookkeeping variables to the values recorded in the opaque
data structure pointed to by state.
RETURN VALUE
On success, malloc_get_state() returns a pointer to a newly allocated opaque data structure. On error (for example, memory could not be
allocated for the data structure), malloc_get_state() returns NULL.
On success, malloc_set_state() returns 0. If the implementation detects that state does not point to a correctly formed data structure,
malloc_set_state() returns -1. If the implementation detects that the version of the data structure referred to by state is a more recent
version than this implementation knows about, malloc_set_state() returns -2.
CONFORMING TO
These functions are GNU extensions.
NOTES
These functions are useful when using this malloc(3) implementation as part of a shared library, and the heap contents are saved/restored
via some other method. This technique is used by GNU Emacs to implement its "dumping" function.
Hook function pointers are never saved or restored by these functions, with two exceptions: if malloc checking (see mallopt(3)) was in use
when malloc_get_state() was called, then malloc_set_state() resets malloc checking hooks if possible; if malloc checking was not in use in
the recorded state, but the caller has requested malloc checking, then the hooks are reset to 0.
SEE ALSO malloc(3), mallopt(3)GNU 2014-06-13 MALLOC_GET_STATE(3)