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diff --git a/man3/getauxval.3 b/man3/getauxval.3 deleted file mode 100644 index c41cce0..0000000 --- a/man3/getauxval.3 +++ /dev/null @@ -1,272 +0,0 @@ -'\" t -.\" Copyright 2012 Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" See also https://lwn.net/Articles/519085/ -.\" -.TH getauxval 3 2023-10-31 "Linux man-pages 6.7" -.SH NAME -getauxval \- retrieve a value from the auxiliary vector -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <sys/auxv.h> -.P -.BI "unsigned long getauxval(unsigned long " type ); -.fi -.SH DESCRIPTION -The -.BR getauxval () -function retrieves values from the auxiliary vector, -a mechanism that the kernel's ELF binary loader -uses to pass certain information to -user space when a program is executed. -.P -Each entry in the auxiliary vector consists of a pair of values: -a type that identifies what this entry represents, -and a value for that type. -Given the argument -.IR type , -.BR getauxval () -returns the corresponding value. -.P -The value returned for each -.I type -is given in the following list. -Not all -.I type -values are present on all architectures. -.TP -.B AT_BASE -The base address of the program interpreter (usually, the dynamic linker). -.TP -.B AT_BASE_PLATFORM -A pointer to a string (PowerPC and MIPS only). -On PowerPC, this identifies the real platform; may differ from -.BR AT_PLATFORM "." -On MIPS, -.\" commit e585b768da111f2c2d413de6214e83bbdfee8f22 -this identifies the ISA level (since Linux 5.7). -.TP -.B AT_CLKTCK -The frequency with which -.BR times (2) -counts. -This value can also be obtained via -.IR sysconf(_SC_CLK_TCK) . -.TP -.B AT_DCACHEBSIZE -The data cache block size. -.TP -.B AT_EGID -The effective group ID of the thread. -.TP -.B AT_ENTRY -The entry address of the executable. -.TP -.B AT_EUID -The effective user ID of the thread. -.TP -.B AT_EXECFD -File descriptor of program. -.TP -.B AT_EXECFN -A pointer to a string containing the pathname used to execute the program. -.TP -.B AT_FLAGS -Flags (unused). -.TP -.B AT_FPUCW -Used FPU control word (SuperH architecture only). -This gives some information about the FPU initialization -performed by the kernel. -.TP -.B AT_GID -The real group ID of the thread. -.TP -.B AT_HWCAP -An architecture and ABI dependent bit-mask whose settings -indicate detailed processor capabilities. -The contents of the bit mask are hardware dependent -(for example, see the kernel source file -.I arch/x86/include/asm/cpufeature.h -for details relating to the Intel x86 architecture; the value -returned is the first 32-bit word of the array described there). -A human-readable version of the same information is available via -.IR /proc/cpuinfo . -.TP -.BR AT_HWCAP2 " (since glibc 2.18)" -Further machine-dependent hints about processor capabilities. -.TP -.B AT_ICACHEBSIZE -The instruction cache block size. -.\" .TP -.\" .BR AT_IGNORE -.\" .TP -.\" .BR AT_IGNOREPPC -.\" .TP -.\" .BR AT_NOTELF -.TP -.\" Kernel commit 98a5f361b8625c6f4841d6ba013bbf0e80d08147 -.B AT_L1D_CACHEGEOMETRY -Geometry of the L1 data cache, encoded with the cache line size in bytes -in the bottom 16 bits and the cache associativity in the next 16 bits. -The associativity is such that if N is the 16-bit value, -the cache is N-way set associative. -.TP -.B AT_L1D_CACHESIZE -The L1 data cache size. -.TP -.B AT_L1I_CACHEGEOMETRY -Geometry of the L1 instruction cache, encoded as for -.BR AT_L1D_CACHEGEOMETRY . -.TP -.B AT_L1I_CACHESIZE -The L1 instruction cache size. -.TP -.B AT_L2_CACHEGEOMETRY -Geometry of the L2 cache, encoded as for -.BR AT_L1D_CACHEGEOMETRY . -.TP -.B AT_L2_CACHESIZE -The L2 cache size. -.TP -.B AT_L3_CACHEGEOMETRY -Geometry of the L3 cache, encoded as for -.BR AT_L1D_CACHEGEOMETRY . -.TP -.B AT_L3_CACHESIZE -The L3 cache size. -.TP -.B AT_PAGESZ -The system page size (the same value returned by -.IR sysconf(_SC_PAGESIZE) ). -.TP -.B AT_PHDR -The address of the program headers of the executable. -.TP -.B AT_PHENT -The size of program header entry. -.TP -.B AT_PHNUM -The number of program headers. -.TP -.B AT_PLATFORM -A pointer to a string that identifies the hardware platform -that the program is running on. -The dynamic linker uses this in the interpretation of -.I rpath -values. -.TP -.B AT_RANDOM -The address of sixteen bytes containing a random value. -.TP -.B AT_SECURE -Has a nonzero value if this executable should be treated securely. -Most commonly, a nonzero value indicates that the process is -executing a set-user-ID or set-group-ID binary -(so that its real and effective UIDs or GIDs differ from one another), -or that it gained capabilities by executing -a binary file that has capabilities (see -.BR capabilities (7)). -Alternatively, -a nonzero value may be triggered by a Linux Security Module. -When this value is nonzero, -the dynamic linker disables the use of certain environment variables (see -.BR ld\-linux.so (8)) -and glibc changes other aspects of its behavior. -(See also -.BR secure_getenv (3).) -.TP -.B AT_SYSINFO -The entry point to the system call function in the vDSO. -Not present/needed on all architectures (e.g., absent on x86-64). -.TP -.B AT_SYSINFO_EHDR -The address of a page containing the virtual Dynamic Shared Object (vDSO) -that the kernel creates in order to provide fast implementations of -certain system calls. -.TP -.B AT_UCACHEBSIZE -The unified cache block size. -.TP -.B AT_UID -The real user ID of the thread. -.SH RETURN VALUE -On success, -.BR getauxval () -returns the value corresponding to -.IR type . -If -.I type -is not found, 0 is returned. -.SH ERRORS -.TP -.BR ENOENT " (since glibc 2.19)" -.\" commit b9ab448f980e296eac21ac65f53783967cc6037b -No entry corresponding to -.I type -could be found in the auxiliary vector. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR getauxval () -T} Thread safety MT-Safe -.TE -.SH STANDARDS -GNU. -.SH HISTORY -glibc 2.16. -.SH NOTES -The primary consumer of the information in the auxiliary vector -is the dynamic linker, -.BR ld\-linux.so (8). -The auxiliary vector is a convenient and efficient shortcut -that allows the kernel to communicate a certain set of standard -information that the dynamic linker usually or always needs. -In some cases, the same information could be obtained by system calls, -but using the auxiliary vector is cheaper. -.P -The auxiliary vector resides just above the argument list and -environment in the process address space. -The auxiliary vector supplied to a program can be viewed by setting the -.B LD_SHOW_AUXV -environment variable when running a program: -.P -.in +4n -.EX -$ LD_SHOW_AUXV=1 sleep 1 -.EE -.in -.P -The auxiliary vector of any process can (subject to file permissions) -be obtained via -.IR /proc/ pid /auxv ; -see -.BR proc (5) -for more information. -.SH BUGS -Before the addition of the -.B ENOENT -error in glibc 2.19, -there was no way to unambiguously distinguish the case where -.I type -could not be found from the case where the value corresponding to -.I type -was zero. -.SH SEE ALSO -.BR execve (2), -.BR secure_getenv (3), -.BR vdso (7), -.BR ld\-linux.so (8) |