Originally posted by rajashekaran Hello
when i mentioned 1 byte in malloc function how it stores 580 integers ?
You are not storing 580 integers in one byte. You are walking across memory by advancing the pointer by 1 with each iteration. I am surprised that the program doesn't blow up in a more random fashion.
Come to think of it, you are allocating one byte of memory and the integer data type should take between two and four bytes of memory (depending on system). My FreeBSD machine reports 4 bytes for an integer datatype.
You really should be allocating the proper amount of memory with:
hello sir
since by mentioning a integer pointer and storing the integers
by incrementing the pointer value
then what is the purpose of malloc?
u can decalre it as
in t *p;
several integers can be stored by incrementing the value of p,
hence what is the diffrence between this... (2 Replies)
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... (5 Replies)
Some one please explain me what is Dynamic memory allocation and the use of malloc() function.How do we allocate memory dynamically and also the other way? (3 Replies)
Hey Guys
I am trying to implement the malloc function for my OS class and I am having a little trouble with it. I would be really grateful if I could get some hints on this problem.
So I am using a doubly-linked list as my data structure and I have to allocate memory for it (duh...). The... (1 Reply)
Hey Guys
Some of my friends have got together and we are trying to write a basic kernel similar to Linux. I am trying to implement the malloc function in C and I am using a doubly linked list as the primary data structure. I need to allocate memory for this link list (duh...) and I don't feel... (2 Replies)
In a 'C' program,when I am trying to allocate memory with the help of malloc () function, it is allocating the memory up to a certain limit for e.g. in my case, it is 670 MB (approx). malloc() returns NULL if I allocate more than this amount of memory.When I tried
to allocate memory in chunks of... (1 Reply)
Which one is faster among malloc and new?
My understanding is that since new also has to call constructors after allocating memory it must be slower than malloc.
Am I correct? (1 Reply)
Good day! I'm a newbie in C. I'm trying to get an unlimited input from the user using malloc then printing the inputs after the user presses enter. My code works, but there's a warning that I don't know how to fix. Please help me. Thank you.
Here's my code:
#include <stdio.h>
#include... (6 Replies)
Hi All,
I am using malloc function for allocating dynamic memory.
When I am using below code on Linux server its working fine, but When I am trying the same code on HP UNIX server its returning NULL.
below is a fragment of code in which it is giving problem.
tmp = (format_tree... (4 Replies)
Discussion started by: Taher Saifuddin
4 Replies
LEARN ABOUT HPUX
datalock
datalock(3C)datalock(3C)NAME
datalock() - lock process into memory after allocating data and stack space
SYNOPSIS DESCRIPTION
allocates at least datsiz bytes of data space and stsiz bytes of stack space, then locks the program in memory. The data space is allo-
cated by (see malloc(3C)). After the program is locked, this space is released by (see malloc(3C)), making it available for use. This
allows the calling program to use that much space dynamically without receiving the signal.
The effective user ID of the calling process must be super-user or be a member of or have an effective group ID of a group having
PRIV_MLOCK access to use this call (see setprivgrp(2) in getprivgrp(2)).
EXAMPLES
The following call to allocates 4096 bytes of data space and 2048 bytes of stack space, then locks the process in memory:
RETURN VALUE
returns -1 if cannot allocate enough memory or if returned an error (see plock(2)).
WARNINGS
Multiple datalocks cannot be the same as one big one.
Methods for calculating the required size are not yet well developed.
AUTHOR
was developed by HP.
SEE ALSO getprivgrp(2), plock(2), thread_safety(5).
datalock(3C)