How to compile proc program in SCO unix 6.0

Hi
I install SCO unix 6.0 on server and run oracle7.0 on it my oracle form and sql, pl/sql running smoothly. but when try to complie new proc program system gives error
UX:acomp: ERROR: "./function.h", line 2: cannot find include file: <oldstyle/string.h>
UX:acomp: WARNING: "./function.h", line 268: improper pointer/integer combination: op "="
*** Error code 1 (bu21)
UX:make: ERROR: fatal error.
any one have any idea to resolve the problem, allready complied run smooth
any one who have work experience work on oracle 7.0 with sco unix 6.0 I am already work on oracle7.0 with sco unix 5.06
thanks

You do not mention what compiler you are using nor its version... Oracle needs C ANSI ( when a C compiler is needed...)
and Oracle 7.0 is not Y2K compliant... I learned and worked with oracle 6, 7,8...
I never had a 7.0, but a 7.1.X ... All our vintage oracle databases were migrated to the first supported Y2K version in 98-99 that meant 7.2.3, and 7.3.X for those not having tricky stuff included ( like apps using triggers, that was a pain for me...) all using forms2 where migrated to 7.2.3

Does "oldstyle/string.h" exist anywhere on your system?

Which release of SCO 6.0 ?
There are 3 C compilers available.
gcc-2.95 from the Skunkware collection
cc from the SCO Development system
gcc-7.3.0 (2017) included with Openserver 6 Definitive Release 2 (2021)