pread(2) System Calls Manual pread(2) pread, pwrite - LIBRARY Standard C library (libc, -lc) #include ssize_t pread(int fd, void buf[.count], size_t count, off_t offset); ssize_t pwrite(int fd, const void buf[.count], size_t count, off_t offset); glibc (. feature_test_macros(7)): pread(), pwrite(): _XOPEN_SOURCE >= 500 || /* glibc 2.12: */ _POSIX_C_SOURCE >= 200809L pread() count fd, offset ( ), , buf. . pwrite() count buf fd , offset. . , fd, . pread() ( ), pwrite() -- . , ( read(2) write(2)). -1, errno . pread() errno , read(2) lseek(2). pwrite() errno , write(2) lseek(2). POSIX.1-2008. POSIX.1-2001. Added in Linux 2.1.60; the entries in the i386 system call table were added in Linux 2.1.69. C library support (including emulation using lseek(2) on older kernels without the system calls) was added in glibc 2.1. C On Linux, the underlying system calls were renamed in Linux 2.6: pread() became pread64(), and pwrite() became pwrite64(). The system call numbers remained the same. The glibc pread() and pwrite() wrapper functions transparently deal with the change. 32- , syscall(2). pread() pwrite() . - , . POSIX , O_APPEND , pwrite() . Linux, O_APPEND, pwrite() , offset. . lseek(2), read(2), readv(2), write(2) Alexey, Azamat Hackimov , kogamatranslator49 , Kogan, Max Is , Yuri Kozlov ; GNU 3 , . . , , . Linux man-pages 6.06 31 2023 . pread(2)