Popen problem


 
Thread Tools Search this Thread
Top Forums Programming Popen problem
# 1  
Old 02-19-2015
Popen problem

Hello all,

I am reading a huge zip file in POPEN process and then writting that to a normal file which of 2GB. Now the process is failing when I looked for the cause someother process comming in after I read my file and it is deleting the zip. But in theory the popen command should read the zip file in memory and even a process deletes that it should have not failed right. Do you know what is the causing the process to fail

Thanks
Arun

Last edited by arunkumar_mca; 02-23-2015 at 09:25 AM..
# 2  
Old 02-19-2015
Quote:
Originally Posted by arunkumar_mca
I am reading a huge zip file in POPEN process and then writing that to a normal file which of 2GB. Now the process is failing when I looked for the cause some other process coming in after I read my file and it is deleting the zip. But in theory the popen command should read the zip file in memory and even a process deletes that it should have not failed right. Do you know what is the causing the process to fail
First off, is this when it's running in Windows or not? Windows does not handle deletion the same way.

Second, in what way does it actually fail? What happens?

Third, your last printf seems a little wonky:

Code:
::sprintf(szBuf,"(%d) Total  %.0f",m_nPid,);

Two conversion modifiers %d %f, and only one argument.
# 3  
Old 02-19-2015
Thanks for the reply . my Answers below

1. it is failing only in LINUX

2. the process is not failing, it just give this error . (Note this error is not comming from code)
error: zipfile read error
(23409) Total records read 23897400


3. Sorry my type please read the last code as

Code:
::sprintf(szBuf,"(%d) Total records read      %.0f",m_nPid,m_Counter);

# 4  
Old 02-23-2015
Here is what I found. The zip file I am trying to remove is on NAS. Actually when we remove the file from same host then the error is not happening I mean run the unzip on one host and remove the zip file same host then the error is not happening. If I run the process in one host and remove the file from other host which has the same NAS mount then the error is happening .

THanks,
Arun
# 5  
Old 02-23-2015
Which version of NFS are you using on the clients? NFSv3 or NFSv4? It can be different on different clients.

NFSv3 is completely stateless - it has no concept of an open file. If the client that is seeing the error is using NFSv3 to mount the file system, any other host is free to delete the file.

NFSv4 is supposed to maintain file open and close state, but since it's much more maintenance-intensive I've always just used NFSv3 - my NFSv4 experiences haven't been good.
# 6  
Old 02-23-2015
Thanks .. How to check whether I am using NFSV3 or NFSv4

found using mount -v Smilie thanks anyway

Last edited by arunkumar_mca; 02-23-2015 at 09:47 AM..
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Programming

question about system and popen in C

in man system it talks about SIGCHLD will be blocked, and SIGINT and SIGQUIT will be ignored. Does this signal stuff also happen in popen command? (even though man popen says nothing about signals) also if I am not using wait(&status) and I am using waitpid(pid, NULL, 0) how would... (1 Reply)
Discussion started by: omega666
1 Replies

2. Programming

question about popen in C

does popen print out the executed string result in stdout, or just evaluate it and not print the result? (30 Replies)
Discussion started by: omega666
30 Replies

3. Programming

segmentation fault while using popen

hi, i am trying to use popen to run a grep process and check if the pattern exists in the file that i am searching in. i am getting segmentation fault when i try to execute the following code char *cd; char flag; char hdr_flpsp; char hdr_flpsp2; FILE *fp; printf ("program starts");... (1 Reply)
Discussion started by: sais
1 Replies

4. UNIX for Advanced & Expert Users

popen and pclose solved

Hi I am trying to use popen function with wrtie option to give inputs to ftp command. #include "stdio.h" int main(int argv ,char *argc) { int size=0; char *buf; FILE *fp; fp = popen("ftp","w"); while(getline(&buf,&size,stdin) != -1) write(fp,buf);... (0 Replies)
Discussion started by: kumaran_5555
0 Replies

5. Programming

prolems with pipes and popen in c

Hi! I'm trying to write a c program. The child process must transmit to the parent a file name and the parent must count the lines from the file and return te result to the child. Here is what i've done. It doesn't stop running, I guess. I'm sorry if it's an ugly code, i'm new at this stuff,... (2 Replies)
Discussion started by: alina89
2 Replies

6. Shell Programming and Scripting

Python: popen problems

Hello I'm writing a web server in python(obelisk-http.sourceforge.net) and I'm having a greeat problem with POST method it like that When someone make a POST request to the server it must open the executable(perl/python/.exe/elf) and send to the STANDART in (stdin) the request and get the... (2 Replies)
Discussion started by: sendai
2 Replies

7. Programming

using popen with background process

hi, how to work with a background process without a controlling terminal to make use of popen or system call ? when ever i use popen or system function call in foreground process, there is no problem with respect to that .. but when the same program is run as a background process without a... (7 Replies)
Discussion started by: matrixmadhan
7 Replies

8. Programming

popen and tar, please HELP!

Hi there, I'm facing a problem running the tar command with the popen function. FILE* fp = popen("tar czf - textfile","r") // output this program should give the output to the stdout. I don't know if it is possible and which function like fprint() etc. should I use. I suppose that I... (4 Replies)
Discussion started by: stef83
4 Replies

9. Programming

query in popen

hai friends I have written a tcp chat server in c.. I have designed a cgi program in c to control it... When i try to start the server from the cgi program, it is not starting. Why is that ? I have even tried giving the root ownership for all the programs.. Still its not. I have used the... (1 Reply)
Discussion started by: collins
1 Replies

10. Programming

question about popen();

Hi The following is my program to test popen() routine. The purpose is to print some contents of the corrent directory. But in fact, the output is only one character 'a', which I believe is the first char of the file "a.out". So, can anybody tell me what is wrong about this program?... (2 Replies)
Discussion started by: dell9
2 Replies
Login or Register to Ask a Question