Checking if errno != EINTR: what does it mean?

by

Many system calls will report the EINTR error code if a signal occurred while the system call was in progress. No error actually occurred, it’s just reported that way because the system isn’t able to resume the system call automatically. This coding pattern simply retries the system call when this happens, to ignore the interrupt.

For instance, this might happen if the program makes use of alarm() to run some code asynchronously when a timer runs out. If the timeout occurs while the program is calling write(), we just want to retry the system call (aka read/write, etc).

More Related Contents:

  1. How do I make this Linux program compile? [closed]
  2. How to avoid using printf in a signal handler?
  3. What is the difference between sigaction and signal?
  4. What is the equivalent to Posix popen() in the Win32 API?
  5. How to capture Control+D signal?
  6. How to know linux scheduler time slice?
  7. Segmentation fault handling
  8. What is “:-!!” in C code?
  9. What are vdso and vsyscall?
  10. Building a kernel module from several source files which one of them has the same name as the module
  11. Are there any platforms where using structure copy on an fd_set (for select() or pselect()) causes problems?
  12. How can I convert a file pointer ( FILE* fp ) to a file descriptor (int fd)?
  13. Why am I able to perform floating point operations inside a Linux kernel module?
  14. How to access mmaped /dev/mem without crashing the Linux kernel?
  15. How to get the current time in milliseconds from C in Linux?
  16. How can I get a filename from a file descriptor inside a kernel module?
  17. What is the difference between a Linux platform driver and normal device driver?
  18. Does linux allow any system call to be made from signal handlers?
  19. Linux/POSIX equivalent for Win32’s CreateEvent, SetEvent, WaitForSingleObject
  20. Which thread handles the signal?
  21. Signal queuing in C
  22. How to flush the CPU cache for a region of address space in Linux?
  23. Linux shared memory: shmget() vs mmap()?
  24. How to create a new Linux kernel scheduler
  25. Linux: Why is sig_atomic_t typedef’ed to int?
  26. executing default signal handler
  27. How to use lockdep feature in linux kernel for deadlock detection
  28. /proc/[pid]/pagemaps and /proc/[pid]/maps | linux
  29. How to know if a Linux system call is restartable or not?
  30. How to print exact value of the program counter in C

Leave a Comment