Markur Sens <markursens(at)gmail(dot)com> writes:
> In the “Extending SQL” chapter I see both of these forms are mentioned.
> But can’t find info about when to use which one.
PG_GETARG_TEXT_P returns a traditional-format, 4-byte-header value.
PG_GETARG_TEXT_PP is allowed to return either that or a 1-byte-header
value, in case that's what the input is.
PG_GETARG_TEXT_PP is preferred in new code since it can avoid one
step of palloc-and-copy-the-value; the only real downside is you
have to use the appropriate macros to get the string's start address
and length.
regards, tom lane