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Diffstat (limited to 'man3/lseek64.3')
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diff --git a/man3/lseek64.3 b/man3/lseek64.3 deleted file mode 100644 index 99f080fa1..000000000 --- a/man3/lseek64.3 +++ /dev/null @@ -1,209 +0,0 @@ -'\" t -.\" Copyright 2004 Andries Brouwer <aeb@cwi.nl>. -.\" and Copyright (c) 2020 Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.TH lseek64 3 (date) "Linux man-pages (unreleased)" -.SH NAME -lseek64 \- reposition 64-bit read/write file offset -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.BR "#define _LARGEFILE64_SOURCE" " /* See feature_test_macros(7) */" -.B #include <sys/types.h> -.B #include <unistd.h> -.PP -.BI "off64_t lseek64(int " fd ", off64_t " offset ", int " whence ); -.fi -.SH DESCRIPTION -The -.BR lseek () -family of functions reposition the offset of the open file associated -with the file descriptor -.I fd -to -.I offset -bytes relative to the start, current position, or end of the file, -when -.I whence -has the value -.BR SEEK_SET , -.BR SEEK_CUR , -or -.BR SEEK_END , -respectively. -.PP -For more details, return value, and errors, see -.BR lseek (2). -.PP -Four interfaces are available: -.BR lseek (), -.BR lseek64 (), -.BR llseek (), -and -.BR _llseek (). -.\" -.\" For some background details, see: -.\" https://lore.kernel.org/linux-man/CAKgNAkhNSWR3uYhYYaxx74fZfJ3JrpfAAPVrK0AFk_cAOUsbDg@mail.gmail.com/ -.\" -.SS lseek() -Prototype: -.PP -.in +4n -.EX -.BI "off_t lseek(int " fd ", off_t " offset ", int " whence ); -.EE -.in -.PP -The C library's -.BR lseek () -wrapper function uses the type -.IR off_t . -This is a 32-bit signed type on 32-bit architectures, unless one -compiles with -.PP -.in +4n -.EX -#define _FILE_OFFSET_BITS 64 -.EE -.in -.PP -in which case it is a 64-bit signed type. -.SS lseek64() -Prototype: -.PP -.in +4n -.EX -.BI "off64_t lseek64(int " fd ", off64_t " offset ", int " whence ); -.EE -.in -.PP -The -.BR lseek64 () -library function uses a 64-bit type even when -.I off_t -is a 32-bit type. -Its prototype (and the type -.IR off64_t ) -is available only when one compiles with -.PP -.in +4n -.EX -#define _LARGEFILE64_SOURCE -.EE -.in -.PP -The function -.BR lseek64 () -.\" in glibc 2.0.94, not in glibc 2.0.6 -is available since glibc 2.1. -.\" -.SS llseek() -Prototype: -.PP -.in +4n -.EX -.BI "loff_t llseek(int " fd ", loff_t " offset ", int " whence ); -.EE -.in -.PP -The type -.I loff_t -is a 64-bit signed type. -The -.BR llseek () -library function is available in glibc and works without special defines. -However, the glibc headers do not provide a prototype. -Users should add -the above prototype, or something equivalent, to their own source. -When users complained about data loss caused by a miscompilation of -.BR e2fsck (8), -glibc 2.1.3 added the link-time warning -.PP -.in +4n -"the \`llseek\' function may be dangerous; use \`lseek64\' instead." -.in -.PP -This makes this function unusable if one desires a warning-free -compilation. -.PP -Since glibc 2.28, -.\" glibc commit 5c5c0dd747070db624c8e2c43691cec854f114ef -this function symbol is no longer available to newly linked applications. -.\" -.SS _llseek() -On 32-bit architectures, -this is the system call that is used (by the C library wrapper functions) -to implement all of the above functions. -The prototype is: -.PP -.in +4n -.EX -.BI "int _llseek(int " fd ", off_t " offset_hi ", off_t " offset_lo , -.BI " loff_t *" result ", int " whence ); -.EE -.in -.PP -For more details, see -.BR llseek (2). -.PP -64-bit systems don't need an -.BR _llseek () -system call. -Instead, they have an -.BR lseek (2) -system call that supports 64-bit file offsets. -.\" In arch/x86/entry/syscalls/syscall_32.tbl, -.\" we see the following line: -.\" -.\" 140 i386 _llseek sys_llseek -.\" -.\" This is essentially telling us that 'sys_llseek' (the name generated -.\" by SYSCALL_DEFINE5(llseek...)) is exposed to user-space as system call -.\" number 140, and that system call number will (IIUC) be exposed in -.\" autogenerated headers with the name "__NR__llseek" (i.e., "_llseek"). -.\" The "i386" is telling us that this happens in i386 (32-bit Intel). -.\" There is nothing equivalent on x86-64, because 64 bit systems don't -.\" need an _llseek system call. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.ad l -.nh -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.BR lseek64 () -T} Thread safety MT-Safe -.TE -.hy -.ad -.sp 1 -.SH NOTES -.BR lseek64 () -is one of the functions that was specified in the Large File Summit (LFS) -specification that was completed in 1996. -The purpose of the specification was to provide transitional support -that allowed applications on 32-bit systems to access -files whose size exceeds that which can be represented with a 32-bit -.I off_t -type. -As noted above, this symbol is exposed by header files if the -.B _LARGEFILE64_SOURCE -feature test macro is defined. -ALternatively, on a 32-bit system, the symbol -.I lseek -is aliased to -.I lseek64 -if the macro -.B _FILE_OFFSET_BITS -is defined with the value 64. -.SH SEE ALSO -.BR llseek (2), -.BR lseek (2) |