tools/testing/selftests/proc/fd-002-posix-eq.c
Source file repositories/reference/linux-study-clean/tools/testing/selftests/proc/fd-002-posix-eq.c
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/proc/fd-002-posix-eq.c- Extension
.c- Size
- 1629 bytes
- Lines
- 58
- Domain
- Support Tooling And Documentation
- Bucket
- tools
- Inferred role
- Support Tooling And Documentation: implementation source
- Status
- source implementation candidate
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
assert.hstdio.hsys/types.hsys/stat.hfcntl.hunistd.h
Detected Declarations
function main
Annotated Snippet
// Test that open(/proc/*/fd/*) opens the same file.
#undef NDEBUG
#include <assert.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
int main(void)
{
int fd0, fd1, fd2;
struct stat st0, st1, st2;
char buf[64];
int rv;
fd0 = open("/", O_DIRECTORY|O_RDONLY);
assert(fd0 >= 0);
snprintf(buf, sizeof(buf), "/proc/self/fd/%u", fd0);
fd1 = open(buf, O_RDONLY);
assert(fd1 >= 0);
snprintf(buf, sizeof(buf), "/proc/thread-self/fd/%u", fd0);
fd2 = open(buf, O_RDONLY);
assert(fd2 >= 0);
rv = fstat(fd0, &st0);
assert(rv == 0);
rv = fstat(fd1, &st1);
assert(rv == 0);
rv = fstat(fd2, &st2);
assert(rv == 0);
assert(st0.st_dev == st1.st_dev);
assert(st0.st_ino == st1.st_ino);
assert(st0.st_dev == st2.st_dev);
assert(st0.st_ino == st2.st_ino);
return 0;
}
Annotation
- Immediate include surface: `assert.h`, `stdio.h`, `sys/types.h`, `sys/stat.h`, `fcntl.h`, `unistd.h`.
- Detected declarations: `function main`.
- Atlas domain: Support Tooling And Documentation / tools.
- Implementation status: source implementation candidate.
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.