General

The Linux Standard Base (LSB) defines a system interface for compiled applications and a minimal environment for support of installation scripts. Its purpose is to enable a uniform industry standard environment for high-volume applications conforming to the LSB.

These specifications are composed of two basic parts: A common specification ("LSB-generic") describing those parts of the interface that remain constant across all implementations of the LSB, and an architecture-specific specification ("LSB-arch") describing the parts of the interface that vary by processor architecture. Together, the LSB-generic and the architecture-specific supplement for a single hardware architecture provide a complete interface specification for compiled application programs on systems that share a common hardware architecture.

The LSB-generic document shall be used in conjunction with an architecture-specific supplement. Whenever a section of the LSB-generic specification shall be supplemented by architecture-specific information, the LSB-generic document includes a reference to the architecture supplement. Architecture supplements may also contain additional information that is not referenced in the LSB-generic document.

The LSB contains both a set of Application Program Interfaces (APIs) and Application Binary Interfaces (ABIs). APIs may appear in the source code of portable applications, while the compiled binary of that application may use the larger set of ABIs. A conforming implementation shall provide all of the ABIs listed here. The compilation system may replace (e.g. by macro definition) certain APIs with calls to one or more of the underlying binary interfaces, and may insert calls to binary interfaces as needed.

The LSB is primarily a binary interface definition. Not all of the source level APIs available to applications may be contained in this specification.

Module Specific Scope

This is the IA32 architecture specific Core module of the Linux Standards Base (LSB). This module supplements the generic LSB Core module with those interfaces that differ between architectures.

Interfaces described in this module are mandatory except where explicitly listed otherwise. Core interfaces may be supplemented by other modules; all modules are built upon the core.

Relevant Libraries

The libraries listed in Table 3-1 shall be available on IA32 Linux Standard Base systems, with the specified runtime names. These names override or supplement the names specified in the generic LSB specification. The specified program interpreter, referred to as proginterp in this table, shall be used to load the shared libraries specified by DT_NEEDED entries at run time.

These libraries will be in an implementation-defined directory which the dynamic linker shall search by default.

LSB Implementation Conformance

An implementation shall satisfy the following requirements:

• The implementation shall implement fully the architecture described in the hardware manual for the target processor architecture.

• The implementation shall be capable of executing compiled applications having the format and using the system interfaces described in this document.

• The implementation shall provide libraries containing the interfaces specified by this document, and shall provide a dynamic linking mechanism that allows these interfaces to be attached to applications at runtime. All the interfaces shall behave as specified in this document.

• The map of virtual memory provided by the implementation shall conform to the requirements of this document.

• The implementation's low-level behavior with respect to function call linkage, system traps, signals, and other such activities shall conform to the formats described in this document.

• The implementation shall provide all of the mandatory interfaces in their entirety.

• The implementation may provide one or more of the optional interfaces. Each optional interface that is provided shall be provided in its entirety. The product documentation shall state which optional interfaces are provided.

• The implementation shall provide all files and utilities specified as part of this document in the format defined here and in other referenced documents. All commands and utilities shall behave as required by this document. The implementation shall also provide all mandatory components of an application's runtime environment that are included or referenced in this document.

• The implementation, when provided with standard data formats and values at a named interface, shall provide the behavior defined for those values and data formats at that interface. However, a conforming implementation may consist of components which are separately packaged and/or sold. For example, a vendor of a conforming implementation might sell the hardware, operating system, and windowing system as separately packaged items.

• The implementation may provide additional interfaces with different names. It may also provide additional behavior corresponding to data values outside the standard ranges, for standard named interfaces.

LSB Application Conformance

An application shall satisfy the following requirements:

• Its executable files are either shell scripts or object files in the format defined for the Object File Format system interface.

• Its object files participate in dynamic linking as defined in the Program Loading and Linking System interface.

• It employs only the instructions, traps, and other low-level facilities defined in the Low-Level System interface as being for use by applications.

• If it requires any optional interface defined in this document in order to be installed or to execute successfully, the requirement for that optional interface is stated in the application's documentation.

• It does not use any interface or data format that is not required to be provided by a conforming implementation, unless:

  • If such an interface or data format is supplied by another application through direct invocation of that application during execution, that application is in turn an LSB conforming application.

  • The use of that interface or data format, as well as its source, is identified in the documentation of the application.

• It shall not use any values for a named interface that are reserved for vendor extensions.

Processor Architecture

The IA32 Architecture is specified by the following documents

• The IA-32 Intel® Architecture Software Developer's Manual Volume 1: Basic Architecture

• The IA-32 Intel® Architecture Software Developer's Manual Volume 2: Instruction Set Reference

• The IA-32 Intel® Architecture Software Developer's Manual Volume 3: System Programming Guide

Only the features of the Intel486 processor instruction set may be assumed to be present. An application is responsible for determining if any additional instruction set features are available before using those additional features. If a feature is not present, then the application may not use it.

Only instructions which do not require elevated privileges may be used.

Applications may not make system calls directly. The interfaces in the C library must be used instead.

Applications conforming to this specification must provide feedback to the user if a feature that is required for correct execution of the application is not present. Applications conforming to this specification should attempt to execute in a diminished capacity if a required instruction set feature is not present.

This specfication does not provide any performance guarantees of a conforming system. A system conforming to this specification may be implemented in either hardware or software.

Data Representation

LSB-conforming applications shall use the data representation as defined in Chapter 3 of the System V Application Binary Interface - Intel386 Architecture Processor Supplement.

CPU Registers

Floating Point Registers

Stack Frame

Arguments

Return Values

Virtual Address Space

Processor Execution Mode

Exception Interface

Signal Delivery

Special Registers

Process Stack (on entry)

Auxilliary Vectors

Environment

Code Model Overview/Architecture Constraints

Position-Independent Fucntion Prologue

Data Objects

Function Calls

Branching

Variable Argument List

Dynamic Allocation of Stack Space

Machine Information

LSB-conforming applications shall use the Machine Information as defined in Chapter 4 of the System V Application Binary Interface - Intel386™ Architecture Processor Supplement, Fourth Edition.

Special Sections

Various sections hold program and control information. Sections in the lists bel ow are used by the system and have the indicated types and attributes.

Relocation Types

Types

Flags

Dynamic Section

The following dynamic entries are defined in the System V Application Binary Interface - Intel386™ Architecture Processor Supplement, Fourth Edition.

Global Offset Table

Shared Object Dependencies

Function Addresses

Procedure Linkage Table

Initialization and Termination Functions

Program Interpreter/Dynamic Linker

The LSB specifies the Program Interpreter to be /lib/ld-lsb.so.2.

Interfaces for libc

Table 1-1 defines the library name and shared object name for the libc library

The behavior of the interfaces in this library is specified by the following specifications:

---

Socket Interface

---

Interfaces for Socket Interface

An LSB conforming implementation shall provide the architecture specific functions for Socket Interface specified in Table 1-10, with the full functionality as described in the referenced underlying specification.

Table 1-10. libc - Socket Interface Function Interfaces

__h_errno_location(GLIBC_2.0) [1]	gethostid(GLIBC_2.0) [2]	listen(GLIBC_2.0) [2]	sendmsg(GLIBC_2.0) [2]	socketpair(GLIBC_2.0) [2]
accept(GLIBC_2.0) [2]	gethostname(GLIBC_2.0) [2]	recv(GLIBC_2.0) [2]	sendto(GLIBC_2.0) [2]
bind(GLIBC_2.0) [2]	getpeername(GLIBC_2.0) [2]	recvfrom(GLIBC_2.0) [2]	setsockopt(GLIBC_2.0) [1]
bindresvport(GLIBC_2.0) [1]	getsockname(GLIBC_2.0) [2]	recvmsg(GLIBC_2.0) [2]	shutdown(GLIBC_2.0) [2]
connect(GLIBC_2.0) [2]	getsockopt(GLIBC_2.0) [2]	send(GLIBC_2.0) [2]	socket(GLIBC_2.0) [2]

Referenced Specification(s)

[1]. Linux Standard Base

[2]. ISO/IEC 9945:2003 Portable Operating System(POSIX)and The Single UNIX® Specification(SUS) V3

An LSB conforming implementation shall provide the architecture specific deprecated functions for Socket Interface specified in Table 1-11, with the full functionality as described in the referenced underlying specification.

These interfaces are deprecated, and applications should avoid using them. These interfaces may be withdrawn in future releases of this specification.

Table 1-11. libc - Socket Interface Deprecated Function Interfaces

gethostbyname_r(GLIBC_2.1.2) [1]

Referenced Specification(s)

[1]. Linux Standard Base

---

Regular Expressions

---

Interfaces for Regular Expressions

An LSB conforming implementation shall provide the architecture specific functions for Regular Expressions specified in Table 1-15, with the full functionality as described in the referenced underlying specification.

Table 1-15. libc - Regular Expressions Function Interfaces

regcomp(GLIBC_2.0) [1]

regerror(GLIBC_2.0) [1]

regexec(GLIBC_2.0) [1]

regfree(GLIBC_2.0) [1]

Referenced Specification(s)

[1]. ISO/IEC 9945:2003 Portable Operating System(POSIX)and The Single UNIX® Specification(SUS) V3

An LSB conforming implementation shall provide the architecture specific deprecated functions for Regular Expressions specified in Table 1-16, with the full functionality as described in the referenced underlying specification.

These interfaces are deprecated, and applications should avoid using them. These interfaces may be withdrawn in future releases of this specification.

Table 1-16. libc - Regular Expressions Deprecated Function Interfaces

advance(GLIBC_2.0) [1]

re_comp(GLIBC_2.0) [1]

re_exec(GLIBC_2.0) [1]

step(GLIBC_2.0) [1]

Referenced Specification(s)

[1]. CAE Specification, January 1997, System Interfaces and Headers (XSH),Issue 5 (ISBN: 1-85912-181-0, C606)

An LSB conforming implementation shall provide the architecture specific deprecated data interfaces for Regular Expressions specified in Table 1-17, with the full functionality as described in the referenced underlying specification.

These interfaces are deprecated, and applications should avoid using them. These interfaces may be withdrawn in future releases of this specification.

Table 1-17. libc - Regular Expressions Deprecated Data Interfaces

loc1(GLIBC_2.0) [1]

loc2(GLIBC_2.0) [1]

locs(GLIBC_2.0) [1]

Referenced Specification(s)

[1]. CAE Specification, January 1997, System Interfaces and Headers (XSH),Issue 5 (ISBN: 1-85912-181-0, C606)

---

Time Manipulation

---

Interfaces for Time Manipulation

An LSB conforming implementation shall provide the architecture specific functions for Time Manipulation specified in Table 1-19, with the full functionality as described in the referenced underlying specification.

Table 1-19. libc - Time Manipulation Function Interfaces

adjtime(GLIBC_2.0) [1]	ctime(GLIBC_2.0) [2]	gmtime(GLIBC_2.0) [2]	localtime_r(GLIBC_2.0) [2]	ualarm(GLIBC_2.0) [2]
asctime(GLIBC_2.0) [2]	ctime_r(GLIBC_2.0) [2]	gmtime_r(GLIBC_2.0) [2]	mktime(GLIBC_2.0) [2]
asctime_r(GLIBC_2.0) [2]	difftime(GLIBC_2.0) [2]	localtime(GLIBC_2.0) [2]	tzset(GLIBC_2.0) [2]

Referenced Specification(s)

[1]. Linux Standard Base

[2]. ISO/IEC 9945:2003 Portable Operating System(POSIX)and The Single UNIX® Specification(SUS) V3

An LSB conforming implementation shall provide the architecture specific deprecated functions for Time Manipulation specified in Table 1-20, with the full functionality as described in the referenced underlying specification.

These interfaces are deprecated, and applications should avoid using them. These interfaces may be withdrawn in future releases of this specification.

Table 1-20. libc - Time Manipulation Deprecated Function Interfaces

adjtimex(GLIBC_2.0) [1]

Referenced Specification(s)

[1]. Linux Standard Base

An LSB conforming implementation shall provide the architecture specific data interfaces for Time Manipulation specified in Table 1-21, with the full functionality as described in the referenced underlying specification.

Table 1-21. libc - Time Manipulation Data Interfaces

__daylight(GLIBC_2.0) [1]	__tzname(GLIBC_2.0) [1]	timezone(GLIBC_2.0) [2]
__timezone(GLIBC_2.0) [1]	daylight(GLIBC_2.0) [2]	tzname(GLIBC_2.0) [2]

Referenced Specification(s)

[1]. Linux Standard Base

[2]. ISO/IEC 9945:2003 Portable Operating System(POSIX)and The Single UNIX® Specification(SUS) V3

Data Definitions for libc

This section defines global identifiers and their values that are associated with interfaces contained in libc. These definitions are organized into groups that correspond to system headers. This convention is used as a convenience for the reader, and does not imply the existence of these headers, or their content.

These definitions are intended to supplement those provided in the referenced underlying specifications.

This specification uses ISO/IEC 9899 C Language as the reference programming language, and data definitions are specified in ISO C format. The C language is used here as a convenient notation. Using a C language description of these data objects does not preclude their use by other programming languages.

#define EDEADLOCK	EDEADLK

typedef long long intmax_t;
typedef unsigned int uintptr_t;
typedef unsigned long long uintmax_t;
typedef unsigned long long uint64_t;

#define LONG_MAX	0x7FFFFFFFL
#define ULONG_MAX	0xFFFFFFFFUL

#define CHAR_MAX	SCHAR_MAX
#define CHAR_MIN	SCHAR_MIN

typedef int __jmp_buf[6];

struct sigaction
{
  union
  {
    sighandler_t _sa_handler;
    void (*_sa_sigaction) (int, siginfo_t *, void *);
  }
  __sigaction_handler;
  sigset_t sa_mask;
  unsigned long sa_flags;
  void (*sa_restorer) (void);
}
 ;
#define MINSIGSTKSZ	2048
#define SIGSTKSZ	8192

struct _fpreg
{
  unsigned short significand[4];
  unsigned short exponent;
}
 ;
struct _fpxreg
{
  unsigned short significand[4];
  unsigned short exponent;
  unsigned short padding[3];
}
 ;
struct _xmmreg
{
  unsigned long element[4];
}
 ;

struct _fpstate
{
  unsigned long cw;
  unsigned long sw;
  unsigned long tag;
  unsigned long ipoff;
  unsigned long cssel;
  unsigned long dataoff;
  unsigned long datasel;
  struct _fpreg _st[8];
  unsigned short status;
  unsigned short magic;
  unsigned long _fxsr_env[6];
  unsigned long mxcsr;
  unsigned long reserved;
  struct _fpxreg _fxsr_st[8];
  struct _xmmreg _xmm[8];
  unsigned long padding[56];
}
 ;

struct sigcontext
{
  unsigned short gs;
  unsigned short __gsh;
  unsigned short fs;
  unsigned short __fsh;
  unsigned short es;
  unsigned short __esh;
  unsigned short ds;
  unsigned short __dsh;
  unsigned long edi;
  unsigned long esi;
  unsigned long ebp;
  unsigned long esp;
  unsigned long ebx;
  unsigned long edx;
  unsigned long ecx;
  unsigned long eax;
  unsigned long trapno;
  unsigned long err;
  unsigned long eip;
  unsigned short cs;
  unsigned short __csh;
  unsigned long eflags;
  unsigned long esp_at_signal;
  unsigned short ss;
  unsigned short __ssh;
  struct _fpstate *fpstate;
  unsigned long oldmask;
  unsigned long cr2;
}
 ;

typedef unsigned int size_t;
typedef int ptrdiff_t;

#define FIONREAD	0x541B
#define TIOCNOTTY	0x5422

struct ipc_perm
{
  key_t __key;
  uid_t uid;
  gid_t gid;
  uid_t cuid;
  gid_t cgid;
  unsigned short mode;
  unsigned short __pad1;
  unsigned short __seq;
  unsigned short __pad2;
  unsigned long __unused1;
  unsigned long __unused2;
}
 ;

#define MCL_CURRENT	1
#define MCL_FUTURE	2

typedef unsigned long msgqnum_t;
typedef unsigned long msglen_t;

struct msqid_ds
{
  struct ipc_perm msg_perm;
  time_t msg_stime;
  unsigned long __unused1;
  time_t msg_rtime;
  unsigned long __unused2;
  time_t msg_ctime;
  unsigned long __unused3;
  unsigned long __msg_cbytes;
  msgqnum_t msg_qnum;
  msglen_t msg_qbytes;
  pid_t msg_lspid;
  pid_t msg_lrpid;
  unsigned long __unused4;
  unsigned long __unused5;
}
 ;

struct semid_ds
{
  struct ipc_perm sem_perm;
  time_t sem_otime;
  unsigned long __unused1;
  time_t sem_ctime;
  unsigned long __unused2;
  unsigned long sem_nsems;
  unsigned long __unused3;
  unsigned long __unused4;
}
 ;

#define SHMLBA	(__getpagesize())

typedef unsigned long shmatt_t;

struct shmid_ds
{
  struct ipc_perm shm_perm;
  int shm_segsz;
  time_t shm_atime;
  unsigned long __unused1;
  time_t shm_dtime;
  unsigned long __unused2;
  time_t shm_ctime;
  unsigned long __unused3;
  pid_t shm_cpid;
  pid_t shm_lpid;
  shmatt_t shm_nattch;
  unsigned long __unused4;
  unsigned long __unused5;
}
 ;

typedef uint32_t __ss_aligntype;

#define _STAT_VER	3

struct stat
{
  dev_t st_dev;
  unsigned short __pad1;
  unsigned long st_ino;
  mode_t st_mode;
  nlink_t st_nlink;
  pid_t st_uid;
  gid_t st_gid;
  dev_t st_rdev;
  unsigned short __pad2;
  off_t st_size;
  blksize_t st_blksize;
  blkcnt_t st_blocks;
  struct timespec st_atim;
  struct timespec st_mtim;
  struct timespec st_ctim;
  unsigned long __unused4;
  unsigned long __unused5;
}
 ;
struct stat64
{
  dev_t st_dev;
  unsigned int __pad1;
  ino_t __st_ino;
  mode_t st_mode;
  nlink_t st_nlink;
  uid_t st_uid;
  gid_t st_gid;
  dev_t st_rdev;
  unsigned int __pad2;
  off64_t st_size;
  blksize_t st_blksize;
  blkcnt64_t st_blocks;
  struct timespec st_atim;
  struct timespec st_mtim;
  struct timespec st_ctim;
  ino64_t st_ino;
}
 ;

struct statvfs
{
  unsigned long f_bsize;
  unsigned long f_frsize;
  fsblkcnt_t f_blocks;
  fsblkcnt_t f_bfree;
  fsblkcnt_t f_bavail;
  fsfilcnt_t f_files;
  fsfilcnt_t f_ffree;
  fsfilcnt_t f_favail;
  unsigned long f_fsid;
  int __f_unused;
  unsigned long f_flag;
  unsigned long f_namemax;
  int __f_spare[6];
}
 ;
struct statvfs64
{
  unsigned long f_bsize;
  unsigned long f_frsize;
  fsblkcnt64_t f_blocks;
  fsblkcnt64_t f_bfree;
  fsblkcnt64_t f_bavail;
  fsfilcnt64_t f_files;
  fsfilcnt64_t f_ffree;
  fsfilcnt64_t f_favail;
  unsigned long f_fsid;
  int __f_unused;
  unsigned long f_flag;
  unsigned long f_namemax;
  int __f_spare[6];
}
 ;

typedef long long int64_t;

typedef int32_t ssize_t;

#define OLCUC	0000002
#define ONLCR	0000004
#define XCASE	0000004
#define NLDLY	0000400
#define CR1	0001000
#define IUCLC	0001000
#define CR2	0002000
#define CR3	0003000
#define CRDLY	0003000
#define TAB1	0004000
#define TAB2	0010000
#define TAB3	0014000
#define TABDLY	0014000
#define BS1	0020000
#define BSDLY	0020000
#define VT1	0040000
#define VTDLY	0040000
#define FF1	0100000
#define FFDLY	0100000

#define VSUSP	10
#define VEOL	11
#define VREPRINT	12
#define VDISCARD	13
#define VWERASE	14
#define VEOL2	16
#define VMIN	6
#define VSWTC	7
#define VSTART	8
#define VSTOP	9

#define IXON	0002000
#define IXOFF	0010000

#define CS6	0000020
#define CS7	0000040
#define CS8	0000060
#define CSIZE	0000060
#define CSTOPB	0000100
#define CREAD	0000200
#define PARENB	0000400
#define PARODD	0001000
#define HUPCL	0002000
#define CLOCAL	0004000
#define VTIME	5

#define ISIG	0000001
#define ICANON	0000002
#define ECHOE	0000020
#define ECHOK	0000040
#define ECHONL	0000100
#define NOFLSH	0000200
#define TOSTOP	0000400
#define ECHOCTL	0001000
#define ECHOPRT	0002000
#define ECHOKE	0004000
#define FLUSHO	0010000
#define PENDIN	0040000
#define IEXTEN	0100000

typedef int greg_t;
#define NGREG	19

typedef greg_t gregset_t[19];

struct _libc_fpreg
{
  unsigned short significand[4];
  unsigned short exponent;
}
 ;

struct _libc_fpstate
{
  unsigned long cw;
  unsigned long sw;
  unsigned long tag;
  unsigned long ipoff;
  unsigned long cssel;
  unsigned long dataoff;
  unsigned long datasel;
  struct _libc_fpreg _st[8];
  unsigned long status;
}
 ;
typedef struct _libc_fpstate *fpregset_t;

typedef struct
{
  gregset_t gregs;
  fpregset_t fpregs;
  unsigned long oldmask;
  unsigned long cr2;
}
mcontext_t;

typedef struct ucontext
{
  unsigned long uc_flags;
  struct ucontext *uc_link;
  stack_t uc_stack;
  mcontext_t uc_mcontext;
  sigset_t uc_sigmask;
  struct _libc_fpstate __fpregs_mem;
}
ucontext_t;

typedef int intptr_t;

struct lastlog
{
  time_t ll_time;
  char ll_line[UT_LINESIZE];
  char ll_host[UT_HOSTSIZE];
}
 ;

struct utmp
{
  short ut_type;
  pid_t ut_pid;
  char ut_line[UT_LINESIZE];
  char ut_id[4];
  char ut_user[UT_NAMESIZE];
  char ut_host[UT_HOSTSIZE];
  struct exit_status ut_exit;
  long ut_session;
  struct timeval ut_tv;
  int32_t ut_addr_v6[4];
  char __unused[20];
}
 ;

struct utmpx
{
  short ut_type;
  pid_t ut_pid;
  char ut_line[UT_LINESIZE];
  char ut_id[4];
  char ut_user[UT_NAMESIZE];
  char ut_host[UT_HOSTSIZE];
  struct exit_status ut_exit;
  long ut_session;
  struct timeval ut_tv;
  int32_t ut_addr_v6[4];
  char __unused[20];
}
 ;

Interfaces for libm

Table 1-28 defines the library name and shared object name for the libm library

The behavior of the interfaces in this library is specified by the following specifications:

Interfaces for libpthread

Table 1-31 defines the library name and shared object name for the libpthread library

The behavior of the interfaces in this library is specified by the following specifications:

Interfaces for libgcc_s

Table 1-33 defines the library name and shared object name for the libgcc_s library

The behavior of the interfaces in this library is specified by the following specifications:

Interface Definitions for libgcc_s

The following interfaces are included in libgcc_s and are defined by this specification. Unless otherwise noted, these interfaces shall be included in the source standard.

Other interfaces listed above for libgcc_s shall behave as described in the referenced base document.

_Unwind_DeleteException

_Unwind_Find_FDE

_Unwind_ForcedUnwind

_Unwind_GetDataRelBase

_Unwind_GetGR

_Unwind_GetIP

_Unwind_GetLanguageSpecificData

_Unwind_GetRegionStart

_Unwind_GetTextRelBase

_Unwind_RaiseException

_Unwind_Resume

_Unwind_SetGR

_Unwind_SetIP

Interfaces for libdl

Table 1-35 defines the library name and shared object name for the libdl library

The behavior of the interfaces in this library is specified by the following specifications:

Interfaces for libcrypt

Table 1-37 defines the library name and shared object name for the libcrypt library

The behavior of the interfaces in this library is specified by the following specifications:

Interfaces for libz

Table 2-1 defines the library name and shared object name for the libz library

Interfaces for libncurses

Table 2-2 defines the library name and shared object name for the libncurses library

Interfaces for libutil

Table 2-3 defines the library name and shared object name for the libutil library

The behavior of the interfaces in this library is specified by the following specifications:

Package Dependencies

The LSB runtime environment shall provide the following dependencies.

Other LSB modules may add additional dependencies; such dependencies shall have the format lsb-module-ia32.

Package Architecture Considerations

All packages must specify an architecture of i486. A LSB runtime environment must accept an architecture of i486 even if the native architecture is different.

The archnum value in the Lead Section shall be 0x0001.