Sigreturn-Oriented Programming (SROP) Vulnerability Analysis We take a look at the main function in IDA graph view and can see that a system call is made. We can quickly determine what function is being called by looking at system call number inside the EAX register before the system call. Also IDA has detected that the write function is called. We can confirm this by looking at system call table which shows that 1 is the system call number for write.