include/uapi/linux/libc-compat.h
Source file repositories/reference/linux-study-clean/include/uapi/linux/libc-compat.h
File Facts
- System
- Linux kernel
- Corpus path
include/uapi/linux/libc-compat.h- Extension
.h- Size
- 7304 bytes
- Lines
- 232
- Domain
- Core OS
- Bucket
- Core Kernel Interface
- Inferred role
- Core OS: implementation source
- Status
- source implementation candidate
Why This File Exists
Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Touches IRQ or DMA behavior; this matters for the representative real-device path.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
#ifndef _UAPI_LIBC_COMPAT_H
#define _UAPI_LIBC_COMPAT_H
/* We have included glibc headers... */
#if defined(__GLIBC__)
/* Coordinate with glibc net/if.h header. */
#if defined(_NET_IF_H) && defined(__USE_MISC)
/* GLIBC headers included first so don't define anything
* that would already be defined. */
#define __UAPI_DEF_IF_IFCONF 0
#define __UAPI_DEF_IF_IFMAP 0
#define __UAPI_DEF_IF_IFNAMSIZ 0
#define __UAPI_DEF_IF_IFREQ 0
/* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS 0
/* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */
#ifndef __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1
#endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO */
#else /* _NET_IF_H */
/* Linux headers included first, and we must define everything
* we need. The expectation is that glibc will check the
* __UAPI_DEF_* defines and adjust appropriately. */
#define __UAPI_DEF_IF_IFCONF 1
#define __UAPI_DEF_IF_IFMAP 1
#define __UAPI_DEF_IF_IFNAMSIZ 1
#define __UAPI_DEF_IF_IFREQ 1
/* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS 1
/* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1
#endif /* _NET_IF_H */
/* Coordinate with glibc netinet/in.h header. */
#if defined(_NETINET_IN_H)
/* GLIBC headers included first so don't define anything
* that would already be defined. */
#define __UAPI_DEF_IN_ADDR 0
#define __UAPI_DEF_IN_IPPROTO 0
#define __UAPI_DEF_IN_PKTINFO 0
#define __UAPI_DEF_IP_MREQ 0
#define __UAPI_DEF_SOCKADDR_IN 0
#define __UAPI_DEF_IN_CLASS 0
#define __UAPI_DEF_IN6_ADDR 0
/* The exception is the in6_addr macros which must be defined
* if the glibc code didn't define them. This guard matches
* the guard in glibc/inet/netinet/in.h which defines the
* additional in6_addr macros e.g. s6_addr16, and s6_addr32. */
#if defined(__USE_MISC) || defined (__USE_GNU)
#define __UAPI_DEF_IN6_ADDR_ALT 0
#else
#define __UAPI_DEF_IN6_ADDR_ALT 1
#endif
#define __UAPI_DEF_SOCKADDR_IN6 0
#define __UAPI_DEF_IPV6_MREQ 0
#define __UAPI_DEF_IPPROTO_V6 0
#define __UAPI_DEF_IPV6_OPTIONS 0
#define __UAPI_DEF_IN6_PKTINFO 0
#define __UAPI_DEF_IP6_MTUINFO 0
#else
/* Linux headers included first, and we must define everything
* we need. The expectation is that glibc will check the
* __UAPI_DEF_* defines and adjust appropriately. */
#define __UAPI_DEF_IN_ADDR 1
#define __UAPI_DEF_IN_IPPROTO 1
#define __UAPI_DEF_IN_PKTINFO 1
#define __UAPI_DEF_IP_MREQ 1
#define __UAPI_DEF_SOCKADDR_IN 1
#define __UAPI_DEF_IN_CLASS 1
#define __UAPI_DEF_IN6_ADDR 1
/* We unconditionally define the in6_addr macros and glibc must
* coordinate. */
#define __UAPI_DEF_IN6_ADDR_ALT 1
#define __UAPI_DEF_SOCKADDR_IN6 1
#define __UAPI_DEF_IPV6_MREQ 1
#define __UAPI_DEF_IPPROTO_V6 1
#define __UAPI_DEF_IPV6_OPTIONS 1
#define __UAPI_DEF_IN6_PKTINFO 1
Annotation
- Atlas domain: Core OS / Core Kernel Interface.
- Implementation status: source implementation candidate.
- IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.