Sponsored Content
Top Forums Programming Pointer addresses in multiples of 32 ? Post 302426351 by bigearsbilly on Tuesday 1st of June 2010 03:33:13 PM
Old 06-01-2010
Quote:
Originally Posted by cyler
Code:
size_t d = c - a;

memset(a, '-', d);

you can't mess about with memory like this and get away with it.
it may work once or twice, but it will cause a seg fault one day.

you cannot make assumptions about how malloc works
or where memory is allocated.
:-)
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

How to sort multiples clolumns of a file?

Hi all! here is the file i am trying to sort : GREIMBAJ00;BAN_CAV;Loader.sh;2003/06/13;17:04:04 GREIMBAJ00;PER_COT;Loader.sh;2003/06/13;17:04:16 GREIMBAJ00;PER_COT;Traitement.sh;2003/06/13;17:04:18 GREIMBAJ00;BAN_PAK;Loader.sh;2003/06/13;17:04:11... (3 Replies)
Discussion started by: HowardIsHigh
3 Replies

2. UNIX for Dummies Questions & Answers

Email multiples attachment files

I have a program the will split a large file into smaller files. It works great. I, however, have problem of email these file out to other people: I may have 1 or more files afer SPLIT datafileaa datafileab datafileac manually: mailx -s "data" email@email.com<datafileaa mailx -s... (5 Replies)
Discussion started by: bobo
5 Replies

3. Programming

pass a pointer-to-pointer, or return a pointer?

If one wants to get a start address of a array or a string or a block of memory via a function, there are at least two methods to achieve it: (1) one is to pass a pointer-to-pointer parameter, like: int my_malloc(int size, char **pmem) { *pmem=(char *)malloc(size); if(*pmem==NULL)... (11 Replies)
Discussion started by: aaronwong
11 Replies

4. UNIX for Dummies Questions & Answers

Using cp for copying multiples files

Hi all, I've got this question about using cp for copying multiples files from the same source directory to another directory, considering that my working directory ain't the same of the source directory. Let me give you a simple example what I'm talking about: Suppose the following files... (2 Replies)
Discussion started by: chapeupreto
2 Replies

5. Shell Programming and Scripting

multiples menu in ksh

Hi, IS possible in ksh to make multiples menus? For example: My menu. 1)Option1 1.1)Option1.1 2.3)Option1.2 2)Option2 2.1)Option2.1 . . . x)Exit I've tried with case but no success. Thanks in advance. (3 Replies)
Discussion started by: iga3725
3 Replies

6. Shell Programming and Scripting

join multiples seds

Hi I have this string with 3 seds.. cat /tmp/roletmp|sed "s/$role2del//" | sed "s/,,/,/" |sed "s/^,//" |sed 's/,$//' How can I join these 3 seds in one? regards Israel. (3 Replies)
Discussion started by: iga3725
3 Replies

7. Programming

multiples of 10 in java

Hi Guys, I wonder how can I determine when a given number is a multiple of another one in java. Let's say if I have 27 how can I determine whether is multiple of 5 using java programming. Thanks. (1 Reply)
Discussion started by: arizah
1 Replies

8. UNIX for Dummies Questions & Answers

[Solved] lost multiples modules

hi guys I got linux Centos 5.5 on grub I got the latest kernel and updates which I really don't know what I did and I lost a lot of modules and my system is not working properly old kernel modules - this kernel is working fine # lsmod Module Size Used by autofs4 ... (0 Replies)
Discussion started by: karlochacon
0 Replies

9. Shell Programming and Scripting

awk on multiples files

Ques from newbie I want to total column X from large number of files, and view totals for each file separately with the filename. I have tried: for i in `ls -1 *.pattern`; do cat "$i" | awk '{SUM += $4} END { printf("%8d\t%8d\n", $i,SUM) }'; done does not work. appreciate your help (5 Replies)
Discussion started by: analyst
5 Replies

10. UNIX for Dummies Questions & Answers

Separate file into multiples Linux

Hi guys I am newbie in using linux, how can i Separate file into multiples linux. I want the lines with same parent and id numbers print out into same files. For example Gm17 5135289 5136789 . Parent=533;ID=534;Name=Glyma17g07060 - Gm17 5135289 5136789 . ... (2 Replies)
Discussion started by: grace_shen
2 Replies
memory(3)						     Library Functions Manual							 memory(3)

Name
       memccpy, memchr, memcmp, memcpy, memmove, memset - memory operations

Syntax
       #include <string.h>

       void *memccpy (s1, s2, c, n)
       void *s1, *s2;
       int c;
       size_t n;

       void *memchr (s, c, n)
       void *s;
       int c;
       size_t n;

       int memcmp (s1, s2, n)
       void *s1, *s2;
       size_t n;

       void *memcpy (s1, s2, n)
       void *s1, *s2;
       size_t n;

       void *memset (s, c, n)
       void *s;
       int c;
       size_t n;

       void *memmove (s1, s2, n)
       void *s1, *s2;
       size_t n;

Description
       These functions operate efficiently on memory areas (arrays of characters bounded by a count, not terminated by a null character).  They do
       not check for the overflow of any receiving memory area.

       The subroutine copies characters from memory area s2 into s1, stopping after the first occurrence of character c has been copied, or  after
       n  characters  have been copied, whichever comes first.	It returns a pointer to the character after the copy of c in s1, or a NULL pointer
       if c was not found in the first n characters of s2.

       The subroutine returns a pointer to the first occurrence of character c in the first n characters of memory area s, or a NULL pointer if  c
       does not occur.

       The  subroutine compares its arguments, looking at the first n characters only, and returns an integer less than, equal to, or greater than
       0, according as s1 is lexicographically less than, equal to, or greater than s2.

       The subroutine copies n characters from memory area s2 to s1.  It returns s1.

       The subroutine is like , except that if s1 and s2 specify overlapping areas, works as if an intermediate buffer is used.

       The subroutine sets the first n characters in memory area s to the value of character c.  It returns s.

Restrictions
       The subroutine uses native character comparison, which is signed on PDP-11s, unsigned on other machines.

       Character movement is performed differently in different implementations of and Thus overlapping moves, using these subroutines, may  yield
       unpredictable results.

																	 memory(3)
All times are GMT -4. The time now is 02:54 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy