If stat() returns -1, THEN errno will be meaningful. Some implementations of libraries don't reset errno unless there actually was an error, meaning you might get the 'leftover' error of a previous call.
This is a very important observation for the original poster. The errno variable may not be accurate if there are more functions being called after the error occurred.
In Tru64 Unix, the 'errno' variable is not thread safe.
Could anybody help me about how to make it thread safe or how to check 'errno' in a Multithreaded program ????
The Programming process is like this.
There are some definite number of threads having their own task.
There is one... (2 Replies)
Hello,
I need to make a lib with pthread, when I run my make file all is good. But when I run my test program, I test errno in the begining and is already set to 251. Is it normal ??? What can I modify in my Makefile to have errno set to 0 ???
Thanks
$make
gcc -D_REENTRANT -shared -fpic... (3 Replies)
How should I use errno in a c program and what info does it have .
I am working with directories and files.
So can any one tell me How to access errno?I am using the stat() function on \etc directory and I am alble to access only the half of the directories.I am not able to access other half and... (6 Replies)
here the program gives a odd result:
#include <stdio.h>
int main(){
perror("first");
perror("next");
return 0;
}
result:
first: Success
next: Illegal seek
why? any resonable explanation? i found no information about this in man pages.
thanks in advance (2 Replies)
from mmap manpage I get it's errors discription:
The addresses specified by the range [off, off + len) are invalid
for filedes.
How could I trigger a ENXIO ? anyone can input the code?
Lei (3 Replies)
Dear all,
CentOS 6
After executing "yum update -y" command I am facing this error. Please help me out.
thanks in advance. Full error & error code is given as follow:
... (7 Replies)
I am calling getpwnam_r with all proper argument as below:-
rv = getpwnam_r(name, result, buffer, buflen);
This program runs fine on sol 8/9/10.
But on sol 11 it returns NULL with errno set to 25
(#define ENOTTY 25 /* Inappropriate ioctl for device */)
All boxes are... (2 Replies)
I am opening a text file using open() system call in O_RDONLY mode.
open() returns me a valid handler but also sets errno to 13 i.e. EACCES(Permission denied).
Question is when open() is returning a valid handler then why does it sets the errno?
Should not errno be set only in case of error... (10 Replies)
I am running the gxemul software under cygwin,
Just when installing the .iso image, I got the error shown in
the picture. Any ideas what's happening?
Thanks
Jack (1 Reply)
Hi, I need to look at a recent copy of /usr/include/errno.h from AIX 7.2 to check some symbols. In particular, I'm curious if it defines EOWNERDEAD and ENOTRECOVERABLE. Can someone who has access to 7.2 please check for me? Thanks! (1 Reply)
Discussion started by: topcat
1 Replies
LEARN ABOUT OSF1
errno
errno(5) File Formats Manual errno(5)NAME
errno - Returns error condition value
SYNOPSIS
#include <errno.h>
DESCRIPTION
The errno external variable contains the most recent error condition set by a function. The symbolic values for errno are listed in the
intro reference page and in the ERRORS section of the individual reference pages for each function.
The exec() functions set errno to a value of 0 (zero) after successful completion. Typically, other functions only set errno to a nonzero
value.
EXAMPLES
The following program uses the value of errno to determine why the requested file could not be opened. If errno has one of the two tested
values, the program prints an appropriate message; otherwise, the program uses the error() function to print out the appropriate message.
This program does not have to set errno to a value of 0 (zero) because errno is tested only if the open() function has failed.
#include <errno.h> #include <stdio.h> #include <string.h> #include <fcntl.h> #include <sys/stat.h> #include <sys/types.h> #define SLENGTH
80
main() {
char filespec[SLENGTH], *eol;
int opret;
while (TRUE) {
printf("Enter file to be checked: ");
fgets(filespec, SLENGTH, stdin);
if ((eol = strchr(filespec, '
')) != NULL) {
*eol = '