#### 24.2.6 Operation Error Signals

These signals are used to report various errors generated by an operation done by the program. They do not necessarily indicate a programming error in the program, but an error that prevents an operating system call from completing. The default action for all of them is to cause the process to terminate.

— Macro: int SIGPIPE

> Broken pipe. If you use pipes or FIFOs, you have to design your application so that one process opens the pipe for reading before another starts writing. If the reading process never starts, or terminates unexpectedly, writing to the pipe or FIFO raises a `SIGPIPE` signal. If `SIGPIPE` is blocked, handled or ignored, the offending call fails with `EPIPE` instead.

> Pipes and FIFO special files are discussed in more detail in Pipes and FIFOs.

> Another cause of `SIGPIPE` is when you try to output to a socket that isn't connected. See Sending Data.

— Macro: int SIGLOST

> Resource lost. This signal is generated when you have an advisory lock on an NFS file, and the NFS server reboots and forgets about your lock.

> On GNU/Hurd systems, `SIGLOST` is generated when any server program dies unexpectedly. It is usually fine to ignore the signal; whatever call was made to the server that died just returns an error.

— Macro: int SIGXCPU

> CPU time limit exceeded. This signal is generated when the process exceeds its soft resource limit on CPU time. See Limits on Resources.

— Macro: int SIGXFSZ

> File size limit exceeded. This signal is generated when the process attempts to extend a file so it exceeds the process's soft resource limit on file size. See Limits on Resources.