releases "better align" with UNIX 03. Previously registered UNIX systems EulerOS EulerOS 2.0 for the x86-64 architecture was registered as UNIX 03 compliant. The UNIX 03 conformance statement shows that the standard C compiler is from the GNU Compiler Collection (), and that the system is a Linux distribution of the Red Hat Enterprise Linux family. The UNIX 03 certification expired in September 2022 and has not been renewed. FTX DNCP Series running FTX Release 3 was registered as UNIX 93 compliant. Inspur K-UX Inspur K-UX 2.0 and 3.0 for the x86-64 architecture were certified as UNIX 03 compliant. The UNIX 03 conformance statement for Inspur K-UX 2.0 and 3.0 shows that the standard C compiler is from the GNU Compiler Collection (), and that the system is a Linux distribution of the Red Hat family. IRIX SGI IRIX 6.5 was registered as UNIX 95 compliant. OS/390 IBM OS/390 was registered as UNIX 95 compliant beginning with the V2R4 release. Reliant UNIX The last Reliant UNIX versions were registered as UNIX 95 compliant (XPG4 hard branding). Solaris Solaris 11.4 was previously registered as UNIX v7 compliant in 2018. Solaris 11 and Solaris 10 were registered as UNIX 03 compliant on 32-bit and 64-bit x86 (X86-64) and SPARC systems. Solaris 8 and 9 were registered as UNIX 98 compliant on 32-bit x86 and SPARC systems; 64-bit x86 systems were not supported. Solaris 2.4 and 2.6, on both x86 and SPARC, were certified to the UNIX 93 and UNIX 95 marks respectively. Solaris 2.5.1 was also registered as UNIX 95 compliant on the PReP PowerPC platform in 1996, but the product was withdrawn before more than a few dozen copies had been sold. Tru64 UNIX Tru64 UNIX V5.1A and later were registered as UNIX 98 compliant. Other Other operating systems previously registered as UNIX 95 or UNIX 93 compliant: NCR UNIX SVR4 NEC UX/4800 Non-registered Unix-like systems Developers and vendors of Unix-like operating systems such as Linux, FreeBSD, and MINIX typically do not certify their distributions and do not install full POSIX utilities by default. For Linux, pax command is usually not installed; furthermore, pax command packages available for Linux often lack pax file format support required by POSIX. Sometimes, SUS compliance can be improved by installing additional packages, but very few Linux systems can be configured to be completely conformant. The Linux Standard Base was formed in 2001 as an attempt