errno

In short, how do you unit test an error condition such as EINTR on a system call. One particular example I'm working on, which could be a case all by itself, is whether it's necessary to call fclose again when it returns EOF with (errno==EINTR). The behavior depends on the implementation of fclose: // Given an open FILE *fp while (fclose(fp)==EOF && errno==EINTR) { errno = 0; } This call can be unsafe if fp freed when EINTR occurs. How can I test the error handling for when (errno==EINTR)? In this particular case, it's not safe to call fclose() again, as the C standard says the stream is

Is it required for me to add a _REENTRANT macro during compile time to make my errno thread safe? If no, is it the case for all versions of gcc / linux / solaris or is it required for certain old versions? I recently tested a piece of code where _REENTRANT was not used and found the errno behaving in an undefined fahsion in multi thread environment? But, after adding _REENTRANT everything was working fine. The Environment was Solaris. But, the discussion here doesn't seem to say it is mandatory to add _REENTRANT. I am a little confused. Also, apart from _REENTRANT should I add be adding any

FastDFS ：java.lang.Exception: getStoreStorage fail, errno code: 28 FastDFS 服务正常，突然报错：java.lang.Exception: getStoreStorage fail, errno code: 28 错误代码28表示 No space left on device。FastDFS 可在 tracker.conf 配置文件中设置 reserved_storage_sapce 参数，即 storage 的预留存储空间大小，默认为10%。如果预留空间小于该设置值，将出现28错误。 解决：1、找到配置文件，手动修改。2、扩大服务器本身存储。3、删掉垃圾文件。 /usr/bin/fdfs_trackerd /etc/fdfs/tracker.conf restart 来源： https://www.cnblogs.com/caonw/p/11903475.html

I am designing a Linux character device driver. I want to set errno when error occurs in ioctl() system call. long my_own_ioctl(struct file *file, unsigned int req, unsigned long arg) { long ret = 0; BOOL isErr = FALSE; // some operation // ... if (isErr) { // set errno // ... <--- What should I do? ret = -1; } return ret; } What should I do to achieve that? Thank you at advance! Please allow me to explain my application with more detail. My device is located in /dev/myCharDev. My user space application is like this: #define _COMMAND (1) #define _ERROR_COMMAND_PARAMETER (-1) int main() { int

问题描述：服务器端执行完send()后调用close()关闭socket，然后exit()正常退出。客户端read()函数返回-1，errno104 : Connection reset by peer，查了一下原因： 这意味着收到了TCP RST包，可以使用tcpdump + wireshark抓包分析，并且连接现在已经关闭，这种情况可能是因为对方崩溃，或者对方调用了close()函数。 解决方法：只要TCP栈的读缓冲里还有未读取（read）数据，则调用close时会直接向对端发送RST。服务器在调用close()函数前，调用shutdown(socket, 2)，先关闭socket的读写功能，这时会向客户端发送FIN包，客户端收到FIN包时read()正常返回0，可以完全读取缓冲数据，问题解决。 close()和shutdown()的区别： 请参考： https://blog.csdn.net/xyyaiguozhe/article/details/30252559 来源： CSDN 作者： ferghs 链接： https://blog.csdn.net/busai2/article/details/81350973

Running the following code on Windows 7 x64 #include <stdio.h> #include <errno.h> int main() { int i; FILE *tmp; for (i = 0; i < 10000; i++) { errno = 0; if(!(tmp = tmpfile())) printf("Fail %d, err %d\n", i, errno); fclose(tmp); } return 0; } Gives errno 13 (Permission denied), on the 637th and 1004th call, it works fine on XP (haven't tried 7 x86). Am I missing something or is this a bug? A bit of a refresher from the manpage of on tmpfile() , which returns a FILE* : The file will be automatically deleted when it is closed or the program terminates. My verdict for this issue: Deleting a file

报错: 　　OSError: [Errno 9] Bad file descriptor 原因: 　　socket对象提前关闭了 来源： https://www.cnblogs.com/weige007/p/11871669.html