mq_open
Implemented in Antinomie 0.7.0 · Syscall list
Synopsis
Section titled “Synopsis”long mq_open(const char *name, int oflag, umode_t mode, struct mq_attr *attr);| Number (x86-64) | 240 |
| ABI | common |
| Kernel entry point | sys_mq_open |
This is the raw kernel prototype from the pinned Linux 6.12.94 schema, not the libc wrapper.
Description
Section titled “Description”Opens or creates a POSIX message queue and returns a descriptor for it.
Arguments
Section titled “Arguments”| Name | Type | Meaning |
|---|---|---|
name (arg0) |
const char * |
Name string (a path, queue name, module name or attribute name depending on the call). |
oflag (arg1) |
int |
Open flags. |
mode (arg2) |
umode_t |
Permission bits (and, for some calls, the file type) for a file or directory being created or changed. |
attr (arg3) |
struct mq_attr * |
Pointer to an attribute structure. |
Return value
Section titled “Return value”On success: A new file descriptor (a non-negative 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 |
|---|---|---|
-13 |
EACCES |
Permission denied. |
-17 |
EEXIST |
The object already exists. |
-2 |
ENOENT |
A path component or the named object does not exist. |
Man page
Section titled “Man page”Captured by Antinomie
Section titled “Captured by Antinomie”Coverage mark: Implemented. Every pointer argument has a capture rule in the pinned kernel patch and none of them records a “no decoder”, “address only” or “not observed” gap on any code path. Individual values can still be incomplete on a particular call; see the capture statuses.
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 |
|---|---|---|---|---|
name (arg0) |
Entry | the pointer itself, as a raw word | args.0, args.raw[0] |
|
| ↳ pointee | Entry | NUL-terminated string, up to 4,096 bytes (PATH_MAX) | arg0.path |
always |
oflag (arg1) |
Entry | raw scalar word | args.1, args.oflag |
|
mode (arg2) |
Entry | raw scalar word | args.2, args.mode |
|
attr (arg3) |
Entry | the pointer itself, as a raw word | args.3, args.raw[3] |
|
| ↳ pointee | Entry | structure mq_attr (fixed size) |
arg3.data |
always |
Filter fields
Section titled “Filter fields”- Result:
ret,syscall.errno,syscall.success,syscall.duration_ns. - Argument words:
args.name(arg0),args.oflag(arg1),args.mode(arg2),args.attr(arg3);args.0toargs.5by position. - Captured strings: the
args.<name>field of a path argument, andargs.path, give the captured text instead of the pointer. - Structure
mq_attrbehindattr(arg3):args.attr.<member>formq_curmsgs,mq_flags,mq_maxmsg,mq_msgsize.
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.