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NAMEsigreturn - return from signal
SYNOPSISIn signal.h Ft int Fn sigreturn const ucontext_t *scp
DESCRIPTIONThe Fn sigreturn system call allows users to atomically unmask, switch stacks, and return from a signal context. The thread's signal mask and stack status are restored from the context structure pointed to by Fa scp . The system call does not return; the users stack pointer, frame pointer, argument pointer, and processor status longword are restored from the context. Execution resumes at the specified pc. This system call is used by the trampoline code and longjmp(3) when returning from a signal to the previously executing program.
RETURN VALUESIf successful, the system call does not return. Otherwise, a value of -1 is returned and errno is set to indicate the error.
ERRORSThe Fn sigreturn system call will fail and the thread context will remain unchanged if one of the following occurs.
- Bq Er EFAULT
- The Fa scp argument points to memory that is not a valid part of the process address space.
- Bq Er EINVAL
- The process status longword is invalid or would improperly raise the privilege level of the process.