It seems like ltrace is showing more parameters then the functions provide, take for instance this
getauxval(31, 0x7ffe5ee5a5c0, 0, 0x7066732e6d657473) = 0x7f4f747cd030
Why are there 4 parameters there, two integers two memory locations rather than one parameter which is all Linux's getauxval seems to support? What's the right way to read the output of ltrace?
I've stumbled upon the same question. After some research and comparison with the source file, I found out that these arguments are the values of the stack variables at the time the function is called. So If you expect (know) your function to have only 1 argument, this will be the first parameter, everything after that are the variables on the function stack