Hello
This is a simple program i carried out in my machine
i dont know how it is working
#include<alloc.h>
#include<stdio.h>
mian()
{
int *p,j;
p= (int*)malloc(1);
for(j=1;j<=580;j++)
{
*p=j;
++p;
}
p=p-580;
for(j=1;j<=580;j++)
{
printf("%d",*p);
} (7 Replies)
Hi All,
In my application malloc is returning NULL even though there is sufficient amount of free memory is available but swap memory is low.
Is this possible that, if free memory is high & swap memory is low, malloc will not be able to allocate memory & return NULL ?:)
Kindly look into... (5 Replies)
Hi All,:)
In my application malloc is returning NULL even though there is sufficient amount of free memory available but the swap memory is low.
Is this possible that, if free memory is high & swap memory is low, malloc will not be able to allocate memory & return NULL ?
Few details:
... (4 Replies)
Hi all,
I am very new to BASH shell programming. I need to return an integer from a function to the caller function. I did this:
but it keeps giving me wrong return:
Can someone help me out here, please?
Thanks (2 Replies)
Hi,
I am having an issue using getservbyport. Here is a little program to demonstrate the problem (removed the includes):
int
main(void) {
struct servent *service;
int memsize = sizeof(struct servent);
service = (struct servent *)malloc(memsize);
... (2 Replies)
Hi,
The following shell script returning null results could you please tell me whats the problem in script,
*********************************
#!/bin/ksh
. $HOME/conf/systemProperties/EnvSetup.properties
a=`date +"%y%m%d"`
set -x
for i in `cat... (2 Replies)
Hi All
In my script, I can call on several functions. I have a logging function that is called by any of these functions. What I would like is some way of identifying which function I am using and pass this to the log function as some parameter.
Is there some built in command or way of... (3 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)
OS : Solaris 10
When I try to get the "echo" service port, getservbyname is returning null.
I checked - /etc/services having an entry for echo -
echo 7/tcp (But still getservbyname returning null)
Any other config required to consider? (1 Reply)
I am calling getpwnam_r with all proper argument as below:-
rv = getpwnam_r(name, result, buffer, buflen);
This program runs fine on sol 8/9/10.
But on sol 11 it returns NULL with errno set to 25
(#define ENOTTY 25 /* Inappropriate ioctl for device */)
All boxes are... (2 Replies)
Discussion started by: Ranajit
2 Replies
LEARN ABOUT PLAN9
malloc
MALLOC(2) System Calls Manual MALLOC(2)NAME
malloc, free, realloc, calloc - memory allocator
SYNOPSIS
#include <u.h>
#include <libc.h>
void* malloc(long size)
void free(void *ptr)
void* realloc(void *ptr, long size)
void* calloc(long nelem, long elsize)
DESCRIPTION
Malloc and free provide a simple memory allocation package. Malloc returns a pointer to a new block of at least size bytes. The block is
suitably aligned for storage of any type of object. No two active pointers from malloc will have the same value.
The argument to free is a pointer to a block previously allocated by malloc; this space is made available for further allocation. It is
legal to free a null pointer; the effect is a no-op.
Realloc changes the size of the block pointed to by ptr to size bytes and returns a pointer to the (possibly moved) block. The contents
will be unchanged up to the lesser of the new and old sizes. The call realloc(0, size) means the same as
Calloc allocates space for an array of nelem elements of size elsize. The space is initialized to zeros. Free frees such a block.
Alef
Except for calloc, these routines are available from Alef; they use the same arena as alloc. Malloc and realloc execute a check when they
fail, rather than return nil. Memory returned by malloc is cleared. Realloc does not guarantee new memory is cleared unless ptr is nil.
SOURCE
/sys/src/libc/port/malloc.c
SEE ALSO brk(2)DIAGNOSTICS
Malloc, realloc and calloc return 0 if there is no available memory. Errstr is likely to be set.
BUGS
The different specification of calloc is bizarre.
User errors can corrupt the storage arena. The most common gaffes are (1) freeing an already freed block, (2) storing beyond the bounds of
an allocated block, and (3) freeing data that was not obtained from the allocator. When malloc and free detect such corruption, they
abort.
MALLOC(2)