04-23-2009
9 More Discussions You Might Find Interesting
1. Programming
When run it, segment fault.
What is wrong?
#include <stdio.h>
#include <stdlib.h>
const int max =20;
//****************************************************
// Input Matrix
//****************************************************
void inMatrixAA(int *AA, int row, int col)... (9 Replies)
Discussion started by: zhshqzyc
9 Replies
2. IP Networking
I do have 2 different segment network which different platform on each segment. E.g. 20 segment, Windows OS can talk to Unix OS and 21 segment practice same rule. Further more, Windows OS from 20 segment can talk to 21 segment other OS but only the UNIX OS in 20 segment fail to talk to 21 segment.... (3 Replies)
Discussion started by: HASM
3 Replies
3. Shell Programming and Scripting
Hey all, could someone please direct me on how to extract a segment from a file between two tags? Thanks! (1 Reply)
Discussion started by: mpang_
1 Replies
4. Programming
I mean, I malloc a segment of memory, maybe 1k maybe 20bytes.. assume the pointer is pMem How can I know the content pMem refered is all Zero or \0 . I know memcmp but the second parameter should another memory address... thanx (4 Replies)
Discussion started by: macroideal
4 Replies
5. Programming
Hi to all.
I'm reciving a "Segment violation" error from this code and I don't know why.
void insertAtEnd(NodeType *pList) {
char element;
printf("Introduce a element: \n");
setbuf(stdin, NULL);
scanf("%c", &element);
//Find the end of the list;
while... (4 Replies)
Discussion started by: daniel.gbaena
4 Replies
6. Programming
Hi,
Whether the following piece of code is placed in the read-only memory of code (text) segment or data segment?
char *a = "Hello";
I am getting two different answers while searching in google :( that's why the confusion is (7 Replies)
Discussion started by: royalibrahim
7 Replies
7. Programming
I always get segment fault, why? can sb help me and modify it, I have spend on much time on
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <string.h>
#define MAX 10
pthread_t thread;
void *thread1()
{
int *a;
int i, n;
... (1 Reply)
Discussion started by: yanglei_fage
1 Replies
8. Shell Programming and Scripting
fuser -OdV /temp
This command returns the output below;
inode=132 size=10871 fd=2 5046330
inode=570 size=292 fd=1 5439528
inode=259 size=2669 fd=1 5570758
inode=759 size=255 fd=1 6226124
inode=636 size=1035 fd=1 ... (8 Replies)
Discussion started by: Daniel Gate
8 Replies
9. Shell Programming and Scripting
I have a file with a combination of binary characters and words, and need to trim out the segment i.e. SleeperThreadAborting {{username::RAB2002}} {{scriptname::scs_get_pending_by_loc}} and put the lists into a text file.
Luckily, the segment I am looking for i.e. has readable words ... (8 Replies)
Discussion started by: Daniel Gate
8 Replies
shmop(2) System Calls Manual shmop(2)
Name
shmop, shmat, shmdt - shared memory operations
Syntax
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
char *shmat (shmid, shmaddr, shmflg)
int shmid;
char *shmaddr;
int shmflg;
int shmdt (shmaddr)
char *shmaddr;
Description
The system call attaches the shared memory segment associated with the shared memory identifier specified by shmid to the data segment of
the calling process. The segment is attached at the address specified by one of the following criteria:
If shmaddr is equal to zero, the segment is attached at the first available address as selected by the system.
If shmaddr is not equal to zero and (shmflg & SHM_RND ) is true, the segment is attached at the address given by (shmaddr- (shmaddr modulus
SHMLBA )).
If shmaddr is not equal to zero and (shmflg & SHM_RND ) is false, the segment is attached at the address given by shmaddr.
The segment is attached for reading if (shmflg & SHM_RDONLY ) is true. Otherwise, it is attached for reading and writing.
The system call detaches from the calling process's data segment the shared memory segment located at the address specified by shmaddr.
Return Values
Upon successful completion, the return values are as follows:
o The system call returns the data segment start address of the attached shared memory segment.
o The system call returns a value of zero (0).
Otherwise, a value of -1 is returned, and errno is set to indicate the error.
Diagnostics
The system call fails and not attach the shared memory segment, if any of the following is true:
[EINVAL] The shmid is not a valid shared memory identifier.
[EACCES] Operation permission is denied to the calling process. For further information, see
[ENOMEM] The available data space is not large enough to accommodate the shared memory segment.
[EINVAL] The shmaddr is not equal to zero, and the value of (shmaddr- (shmaddr modulus SHMLBA )) is an illegal address.
[EINVAL] The shmaddr is not equal to zero, (shmflg & SHM_RND ) is false, and the value of shmaddr is an illegal address.
[EMFILE] The number of shared memory segments attached to the calling process would exceed the system imposed limit.
The fails and does not detach the shared memory segment if:
[EINVAL] The shmaddr is not the data segment start address of a shared memory segment.
See Also
execve(2), exit(2), fork(2), shmctl(2), shmget(2)
shmop(2)