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 CENTOS
tcl_errnoid
Tcl_SetErrno(3) Tcl Library Procedures Tcl_SetErrno(3)__________________________________________________________________________________________________________________________________________________NAME
Tcl_SetErrno, Tcl_GetErrno, Tcl_ErrnoId, Tcl_ErrnoMsg - manipulate errno to store and retrieve error codes
SYNOPSIS
#include <tcl.h>
void
Tcl_SetErrno(errorCode)
int
Tcl_GetErrno()
const char *
Tcl_ErrnoId()
const char *
Tcl_ErrnoMsg(errorCode)
ARGUMENTS
int errorCode (in) A POSIX error code such as ENOENT.
_________________________________________________________________DESCRIPTION
Tcl_SetErrno and Tcl_GetErrno provide portable access to the errno variable, which is used to record a POSIX error code after system calls
and other operations such as Tcl_Gets. These procedures are necessary because global variable accesses cannot be made across module bound-
aries on some platforms.
Tcl_SetErrno sets the errno variable to the value of the errorCode argument C procedures that wish to return error information to their
callers via errno should call Tcl_SetErrno rather than setting errno directly.
Tcl_GetErrno returns the current value of errno. Procedures wishing to access errno should call this procedure instead of accessing errno
directly.
Tcl_ErrnoId and Tcl_ErrnoMsg return string representations of errno values. Tcl_ErrnoId returns a machine-readable textual identifier such
as "EACCES" that corresponds to the current value of errno. Tcl_ErrnoMsg returns a human-readable string such as "permission denied" that
corresponds to the value of its errorCode argument. The errorCode argument is typically the value returned by Tcl_GetErrno. The strings
returned by these functions are statically allocated and the caller must not free or modify them.
KEYWORDS
errno, error code, global variables
Tcl 8.3 Tcl_SetErrno(3)