Whilst creating the function readjust_descr I have stumble across what may be a problem or
something that might just work. I was hoping someone could look at the code below and tell me
if readjust_descr will clear all null pointers from the structure descr_list.
While I am here I might as well ask this also. Thanks a bunch.
Can you show me how to access the second array of a pointer
that calloc returns if I allocated two elements. calloc() allocates memory for an array of nmemb elements.
The man page says it returns a pointer to the allocated member.
I am facing a problem in replacing the file contents by iterating through the list.
My present code:
Code:
#!/bin/bash#
TFILE="/tmp/vinay/testb_1.txt"
while read linedo
aline="$line"
echo $aline
code=`echo $aline|cut -d ',' -f1`
country=`echo $aline|cut -d... (5 Replies)
hi all,
i am writing a ksh script, i am logging into an oracle db via sqlplus and running a select statement but i dont know how i can store the results from the sql so i can iterate over it and do more operations over it. I dont want to write a stored procedure with a cursor since i need to... (2 Replies)
Hey everyone.
Is it possible to use two arrays in a loop?
Basically what I am trying to do is iterate through the elements in an array, and, based on a condition, use the current position in the array to point to that index in the array. Here's the loop structure I'm looking for:
... (1 Reply)
Hello all,
I have a confusion with calloc function :
wz. the difference between the following 2 statemnts:
char *ptr;
char = (char*)calloc(num, sizeof(char));
char = (char*)calloc(num, sizeof(char*));
Am really confused!!!!!
---------- Post updated at 09:32 AM... (1 Reply)
Hello, I am working on a coding project for a class and to test the program I have created, I have come up with 100 different test cases. The program takes four text files as input, so each of the test cases is contained in a folder with four files.
I have a folder called 'tests', within which... (1 Reply)
Hi,
I've recently started using Awk commands as i need it to pull information out of a file and give me the mean value of a series of numbers. Here is the code i run on my Infile and it works just fine.
awk '{if ($1 == "Mam189") print $0}' Infile | awk '{if ($1 != $2) print $0}' | awk... (5 Replies)
Hi , experts.
I work on Linux station (RedHat 5.7), regular user, but have root password.
%> uname -a
Linux ran1log06 2.6.18-238.1.1.el5 #1 SMP Tue Jan 4 13:32:19 EST 2011 x86_64 x86_64 x86_64 GNU/Linux
%> cat /etc/issue
Red Hat Enterprise Linux Client release 5.7 (Tikanga)
Kernel \r on... (5 Replies)
I need to run the same awk function over an entire directly of files.
This is the awk:
awk '{$(NF+1)=1}1'
Is there a way that I can run this command once over all of the files, along the lines of:
awk '{$(NF+1)=1}1' *
so that I do not have to run this several times?
My main concern is... (2 Replies)
Hi,
I am trying to do something similar to the for loop example from KSH For Loop Array: Iterate Through Array Values
$: cat y.ksh
#!/bin/ksh
# set array called nameservers
set -A nameservers 192.168.1.1 192.168.1.5 202.54.1.5
# print all name servers
for i in ${nameservers}
do
... (3 Replies)
Discussion started by: newbie_01
3 Replies
LEARN ABOUT V7
malloc
MALLOC(3) Library Functions Manual MALLOC(3)NAME
malloc, free, realloc, calloc - main memory allocator
SYNOPSIS
char *malloc(size)
unsigned size;
free(ptr)
char *ptr;
char *realloc(ptr, size)
char *ptr;
unsigned size;
char *calloc(nelem, elsize)
unsigned nelem, elsize;
DESCRIPTION
Malloc and free provide a simple general-purpose memory allocation package. Malloc returns a pointer to a block of at least size bytes
beginning on a word boundary.
The argument to free is a pointer to a block previously allocated by malloc; this space is made available for further allocation, but its
contents are left undisturbed.
Needless to say, grave disorder will result if the space assigned by malloc is overrun or if some random number is handed to free.
Malloc allocates the first big enough contiguous reach of free space found in a circular search from the last block allocated or freed,
coalescing adjacent free blocks as it searches. It calls sbrk (see break(2)) to get more memory from the system when there is no suitable
space already free.
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.
Realloc also works if ptr points to a block freed since the last call of malloc, realloc or calloc; thus sequences of free, malloc and
realloc can exploit the search strategy of malloc to do storage compaction.
Calloc allocates space for an array of nelem elements of size elsize. The space is initialized to zeros.
Each of the allocation routines returns a pointer to space suitably aligned (after possible pointer coercion) for storage of any type of
object.
DIAGNOSTICS
Malloc, realloc and calloc return a null pointer (0) if there is no available memory or if the arena has been detectably corrupted by stor-
ing outside the bounds of a block. Malloc may be recompiled to check the arena very stringently on every transaction; see the source code.
BUGS
When realloc returns 0, the block pointed to by ptr may be destroyed.
MALLOC(3)