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
when i run this not even the intial printf message "program starts" is getting displayed. it straight aways throws segmentation fault error.
Can any one please tell me what wrong am i doing here?
Hi,
Why I don't receive a segmentation fault in the following sample.
int main(void)
{
char buff;
sprintf(buff,"Hello world");
printf("%s\n",buff);
}
If I define a buffer of 10 elements and I'm trying to put inside it twelve elements, Should I receive a sigsev... (22 Replies)
Hi,
While comparing primary key data of two tables thr bteq script I am getting this Error. This script is a shell script.
*** Error: The following error was encountered on the output file.
Script.sh: 3043492 Segmentation fault(coredump)
Please let me know how to get through it.
... (5 Replies)
I'm getting a segmentation fault. I'm new to Linux programming. Thanks so much for all of your input.:eek:
#include </usr/include/mysql++/mysql++.h>
#include <stdio.h>
#include <iostream>
#include <sstream>
#include <string.h>
using namespace std;
int outputToImport(const char*... (1 Reply)
This code is causing a segmentation fault and I can't figure out why. I'm new to UNIX and I need to learn how to avoid this segmentation fault thing. Thank you so much. Thanks also for the great answers to my last post.:):b:
int main()
{
mysqlpp::Connection conn(false);
if... (3 Replies)
I use a binary name (ie polo) it gets some parameter , so for debugging normally i do this :
i wrote script for watchdog my app (polo) and check every second if it's not running then start it , the problem is , if my app , remain in state of segmentation fault for a while (ie 15 ... (6 Replies)
Hi Guys,
I just installed and booted a zone called testzone. When I logged in remotely and tried changing to root user I get this error:
"Segmentation fault"
Can someone please help me resolve this?
Thanks alot (2 Replies)
I keep getting this fault on a lot of the codes I write, I'm not exactly sure why so I'd really appreciate it if someone could explain the idea to me.
For example this code
#include <stdio.h>
main()
{
unsigned long a=0;
unsigned long b=0;
int z;
{
printf("Enter two... (2 Replies)
Oddities with gcc, 2.95.3 for the AMIGA and 4.2.1 for MY current OSX 10.14.1...
I am creating a basic calculator for the AMIGA ADE *NIX emulator in C as it does not have one.
Below are two very condensed snippets of which I have added the results inside the each code section.
IMPORTANT!... (11 Replies)
Discussion started by: wisecracker
11 Replies
LEARN ABOUT MOJAVE
popen
POPEN(3) BSD Library Functions Manual POPEN(3)NAME
pclose, popen -- process I/O
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <stdio.h>
FILE *
popen(const char *command, const char *mode);
int
pclose(FILE *stream);
DESCRIPTION
The popen() function ``opens'' a process by creating a bidirectional pipe, forking, and invoking the shell. Any streams opened by previous
popen() calls in the parent process are closed in the new child process. Historically, popen() was implemented with a unidirectional pipe;
hence, many implementations of popen() only allow the mode argument to specify reading or writing, not both. Because popen() is now imple-
mented using a bidirectional pipe, the mode argument may request a bidirectional data flow. The mode argument is a pointer to a null-termi-
nated string which must be 'r' for reading, 'w' for writing, or 'r+' for reading and writing.
The command argument is a pointer to a null-terminated string containing a shell command line. This command is passed to /bin/sh, using the
-c flag; interpretation, if any, is performed by the shell.
The return value from popen() is a normal standard I/O stream in all respects, save that it must be closed with pclose() rather than
fclose(). Writing to such a stream writes to the standard input of the command; the command's standard output is the same as that of the
process that called popen(), unless this is altered by the command itself. Conversely, reading from a ``popened'' stream reads the command's
standard output, and the command's standard input is the same as that of the process that called popen().
Note that output popen() streams are fully buffered, by default.
The pclose() function waits for the associated process to terminate; it returns the exit status of the command, as returned by wait4(2).
RETURN VALUES
The popen() function returns NULL if the fork(2) or pipe(2) calls fail, or if it cannot allocate memory.
The pclose() function returns -1 if stream is not associated with a ``popened'' command, if stream already ``pclosed'', or if wait4(2)
returns an error.
ERRORS
The popen() function does not reliably set errno.
SEE ALSO sh(1), fork(2), pipe(2), wait4(2), fclose(3), fflush(3), fopen(3), stdio(3), system(3)BUGS
Since the standard input of a command opened for reading shares its seek offset with the process that called popen(), if the original process
has done a buffered read, the command's input position may not be as expected. Similarly, the output from a command opened for writing may
become intermingled with that of the original process. The latter can be avoided by calling fflush(3) before popen().
Failure to execute the shell is indistinguishable from the shell's failure to execute command, or an immediate exit of the command. The only
hint is an exit status of 127.
The popen() function always calls sh(1), never calls csh(1).
HISTORY
A popen() and a pclose() function appeared in Version 7 AT&T UNIX.
Bidirectional functionality was added in FreeBSD 2.2.6.
BSD May 3, 1995 BSD