tools/testing/selftests/bpf/io_helpers.c
Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/io_helpers.c
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/bpf/io_helpers.c- Extension
.c- Size
- 450 bytes
- Lines
- 22
- 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
sys/select.hunistd.herrno.h
Detected Declarations
function read_with_timeout
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
#include <sys/select.h>
#include <unistd.h>
#include <errno.h>
int read_with_timeout(int fd, char *buf, size_t count, long usec)
{
const long M = 1000 * 1000;
struct timeval tv = { usec / M, usec % M };
fd_set fds;
int err;
FD_ZERO(&fds);
FD_SET(fd, &fds);
err = select(fd + 1, &fds, NULL, NULL, &tv);
if (err < 0)
return err;
if (FD_ISSET(fd, &fds))
return read(fd, buf, count);
return -EAGAIN;
}
Annotation
- Immediate include surface: `sys/select.h`, `unistd.h`, `errno.h`.
- Detected declarations: `function read_with_timeout`.
- 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.