dup3
Implemented in Antinomie 0.7.0 · Syscall list
Synopsis
Section titled “Synopsis”long dup3(unsigned int oldfd, unsigned int newfd, int flags);| Number (x86-64) | 292 |
| ABI | common |
| Kernel entry point | sys_dup3 |
This is the raw kernel prototype from the pinned Linux 6.12.94 schema, not the libc wrapper.
Description
Section titled “Description”Duplicates a file descriptor onto a number with an optional close-on-exec flag.
Arguments
Section titled “Arguments”| Name | Type | Meaning |
|---|---|---|
oldfd (arg0) |
unsigned int |
File descriptor to duplicate. |
newfd (arg1) |
unsigned int |
Descriptor number to duplicate onto. |
flags (arg2) |
int |
Option flags that change the behavior of the call. |
Return value
Section titled “Return value”On success: the new descriptor number.
In an Antinomie trace the Return column and the ret filter field show the raw kernel return value. On failure that is the negative errno, for example -2 for ENOENT, not the -1 plus errno that the libc wrapper gives. syscall.errno holds the positive errno and syscall.success is false.
Common errors
Section titled “Common errors”| Raw return | Name | Meaning |
|---|---|---|
-9 |
EBADF |
A file descriptor is not valid for this operation. |
-22 |
EINVAL |
An argument is invalid. |
Man page
Section titled “Man page”Captured by Antinomie
Section titled “Captured by Antinomie”Coverage mark: Implemented. All arguments are plain values, recorded as the raw argument words at entry. There is no pointee to copy and no known gap.
Every call is recorded as an Entry record (the six argument words and the pointees copied at entry) and an Exit record (the return value and the pointees copied at exit).
Arguments
Section titled “Arguments”| Argument | When | How | Recorded field key | Condition |
|---|---|---|---|---|
oldfd (arg0) |
Entry | raw scalar word | args.0, args.oldfd |
|
newfd (arg1) |
Entry | raw scalar word | args.1, args.newfd |
|
flags (arg2) |
Entry | raw scalar word; Syscall Trace also decodes it into flag names (cloexec group), listing unknown bits separately |
args.2, args.flags |
Filter fields
Section titled “Filter fields”- Result:
ret,syscall.errno,syscall.success,syscall.duration_ns. - Argument words:
args.oldfd(arg0),args.newfd(arg1),args.flags(arg2);args.0toargs.5by position.
See Syscall Trace filter for the full syntax.
For what the capture statuses mean, see Capture statuses. For what is never recorded, see Known gaps.