1QUERY_MODULE(2) Linux Programmer's Manual QUERY_MODULE(2)
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6 query_module - query the kernel for various bits pertaining to modules
7
9 #include <linux/module.h>
10 int query_module(const char *name, int which, void *buf,
12 size_t bufsize, size_t *ret);
13
15 query_module() requests information from the kernel about loadable mod‐
16 ules. The returned information is placed in the buffer pointed to by
17 buf. The caller must specify the size of buf in bufsize. The precise
18 nature and format of the returned information depend on the operation
19 specified by which. Some operations require name to identify a cur‐
20 rently loaded module, some allow name to be NULL, indicating the kernel
21 proper.
22 The following values can be specified for which:
24 0 Returns success, if the kernel supports query_module(). Used to
26 probe for availability of the system call.
27 QM_MODULES
29 Returns the names of all loaded modules. The returned buffer
30 consists of a sequence of null-terminated strings; ret is set to
31 the number of modules.
32 QM_DEPS
34 Returns the names of all modules used by the indicated module.
35 The returned buffer consists of a sequence of null-terminated
36 strings; ret is set to the number of modules.
37 QM_REFS
39 Returns the names of all modules using the indicated module.
40 This is the inverse of QM_DEPS. The returned buffer consists of
41 a sequence of null-terminated strings; ret is set to the number
42 of modules.
43 QM_SYMBOLS
45 Returns the symbols and values exported by the kernel or the
46 indicated module. The returned buffer is an array of structures
47 of the following form
48 struct module_symbol {
50 unsigned long value;
51 unsigned long name;
52 };
53 followed by null-terminated strings. The value of name is the
55 character offset of the string relative to the start of buf; ret
56 is set to the number of symbols.
57 QM_INFO
59 Returns miscellaneous information about the indicated module.
60 The output buffer format is:
61 struct module_info {
63 unsigned long address;
64 unsigned long size;
65 unsigned long flags;
66 };
67 where address is the kernel address at which the module resides,
69 size is the size of the module in bytes, and flags is a mask of
70 MOD_RUNNING, MOD_AUTOCLEAN, etc. that indicates the current sta‐
71 tus of the module (see the kernel source file include/linux/mod‐
72 ule.h). ret is set to the size of the module_info structure.
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75 On success, zero is returned. On error, -1 is returned and errno is
76 set appropriately.
77
79 EFAULT At least one of name, buf, or ret was outside the program's
80 accessible address space.
81 EINVAL Invalid which; or name is NULL (indicating "the kernel"), but
83 this is not permitted with the specified value of which.
84 ENOENT No module by that name exists.
86 ENOSPC The buffer size provided was too small. ret is set to the mini‐
88 mum size needed.
89 ENOSYS query_module() is not supported in this version of the kernel.
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93 query_module() is Linux-specific.
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96 This system call is only present on Linux up until kernel 2.4; it was
97 removed in Linux 2.6. Some of the information that was available via
98 query_module() can be obtained from /proc/modules, /proc/kallsyms, and
99 /sys/modules.
100
102 create_module(2), delete_module(2), get_kernel_syms(2), init_module(2)
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105 This page is part of release 3.22 of the Linux man-pages project. A
106 description of the project, and information about reporting bugs, can
107 be found at http://www.kernel.org/doc/man-pages/.
108Linux 2007-06-03 QUERY_MODULE(2)