overview of the virtual ELF dynamic shared object NAME vdso - overview of the virtual ELF dynamic shared object SYNOPSIS #include <sys/auxv.h> void *......ms where the C library time () wrapper function invokes an implementation provided by the vdso (7) (so that there is no trap into the kernel), an invalid address may instead tri…...the command line. An example of its use and output is the following: $ ldd /bin/ls linux-vdso.so.1 (0x00007ffcc3563000) libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f87e545…...ffb2c2e000 rw-p 00000000 00:00 0 [stack] 7fffb2d48000-7fffb2d49000 r-xp 00000000 00:00 0 [vdso] The address field is the address space in the process that the mapping occupies. …...ll as fast as possible. (On some architectures, this is done via an implementation in the vdso (7).) The intention of getcpu () is to allow programs to make optimizations with p…...ee also secure_getenv (3).) 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). AT_SYSINFO_EHDR…...ux systems, depending on the architecture, the signal trampoline code lives either in the vdso (7) or in the C library. In the latter case, the C library's sigaction (2) wrapper…...ux systems, depending on the architecture, the signal trampoline code lives either in the vdso (7) or in the C library. In the latter case, the C library's sigaction (2) wrapper…...ifferences On some architectures, an implementation of gettimeofday () is provided in the vdso (7). The kernel accepts NULL for both tv and tz . The timezone argument is ignored…...ifferences On some architectures, an implementation of gettimeofday () is provided in the vdso (7). The kernel accepts NULL for both tv and tz . The timezone argument is ignored…...res per-architecture support, and probably also architecture support for this flag in the vdso (7). CLOCK_TAI (since Linux 3.10; Linux-specific) A nonsettable system-wide clock …...res per-architecture support, and probably also architecture support for this flag in the vdso (7). CLOCK_TAI (since Linux 3.10; Linux-specific) A nonsettable system-wide clock …...res per-architecture support, and probably also architecture support for this flag in the vdso (7). CLOCK_TAI (since Linux 3.10; Linux-specific) A nonsettable system-wide clock …...em call has been deprecated. The modern way to obtain the kernel's unwind data is via the vdso (7). SEE ALSO getauxval (3)...ID of shell 1143 $ pldd $$ # Display DSOs linked into the shell 1143: /usr/bin/bash linux-vdso.so.1 /lib64/libtinfo.so.5 /lib64/libdl.so.2 /lib64/libc.so.6 /lib64/ld-linux-x86-6…...not be the fastest or best way to transition to the kernel, so you might have to refer to vdso (7)), the register used to indicate the system call number, the register(s) used t…...alls (2), getauxval (3), proc (5), feature_test_macros (7), man-pages (7), standards (7), vdso (7)...alls (2), getauxval (3), proc (5), feature_test_macros (7), man-pages (7), standards (7), vdso (7)...e dynamic dependencies of the program: $ cc -g -o prog prog.c -L. -ldemo $ ldd prog linux-vdso.so.1 => (0x00007fff86d66000) libdemo.so.1 => not found libc.so.6 => /lib64/libc.so…...flags: 0x6; PT_GNU_STACK 8: [ 0x600e10; memsz: 1f0] flags: 0x4; PT_GNU_RELRO Name: "linux-vdso.so.1" (4 segments) 0: [0x7ffc6edd1000; memsz: e89] flags: 0x5; PT_LOAD 1: [0x7ffc6…