ChorusOS POSIX APIs and Extensions

The programming environment of POSIX processes includes the standard POSIX APIs and a number of POSIX extensions that can be accessed directly by any process.

POSIX API Libraries

Certain libraries (libc and libstdc++, for example) are implicitly provided when you select the appropriate Imakefile rule (see "The imake Environment"). Other libraries must be explicitly stated in the Imakefile.

The libraries to which a process has access may be either static (.a) or shared (.so). Whether the process uses a static or shared library depends on the rule selected in the Imakefile. Shared processes use libc.so.

The following sections describe all libraries that can be used by a process. Note that the libraries can be accessed by either a user or supervisor actor or process.

libc.a/libc.so and libstdc++.a

The os/lib/libc.a and os/lib/libc.so libraries are automatically included by any process or actor and include the following APIs:

• Private Data API

• LAP API

• MIPC API

• IPC API

• Standard C API

• POSIX I/O API

• POSIX Network API

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Note -

C++ actors or processes have access to the same APIs through the C++ library (os/lib/libstdc++.a).

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Other Libraries

The following libraries can be accessed by either a supervisor or user process or actor. These libraries must be explicitly included in your Imakefile and contain the full pathname.

To add a library to an Imakefile, $(OS_DIR)/lib/lib<libraryname>.a or $(OS_DIR)/lib/lib<libraryname>.so to the relevant rule.

Table 5-1 Static libraries (.a)

Library name and path	Description
os/lib/libcrypt.a	Encryption and decryption library
os/lib/libleamalloc.a	Doug lea malloc library
os/lib/libldap.a	LDAP library
os/lib/libnvpair.a	Solaris-like name/value pair companion library
os/lib/libnsl.a	Network services library (symbolic link to libresolv.a)
os/lib/libpam.a	Interface library for pluggable authentication module (PAM)
os/lib/libresolv.a	Network services library
os/lib/librpc.a	RPC library
os/lib/libpthreads.a	POSIX pthread library
os/lib/libsysevent.a	Solaris-like sysevent API
os/lib/libftpd.a	FTP services
os/lib/libmd.a	Netscape secure hash algorithms.
os/lib/libns.a	ChorusOS Name Service (NS)
os/lib/libtelnetd.a	Telnet services
os/lib/libyp.a	Yellow pages services (xdr_ypXXX)
os/lib/libutil.a	This library includes the functions openpty() and creat().
os/lib/libmsun.a	This library includes the function ilogb() which returns the binary exponent of a non-zero double value.

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Note -

Using the libsysevent.a library dictates that you use the libnvpair.a, librpc.a and libpthreads.a libraries too.

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Table 5-2 Shared libraries (.so)

Library name and path	Description
os/lib/libldap.so	LDAP library
os/lib/libnsl.so	Network services library (symbolic link to libresolv.so)
os/lib/libpam.so	Interface library for PAM
os/lib/libpthreads.so	POSIX pthread library
os/lib/libresolv.so	Network services library
os/lib/librpc.so	RPC library

POSIX Extensions

The extensions to the standard POSIX APIs can be divided into two groups:

• Restricted microkernel calls

• POSIX-like extended services

The restricted microkernel calls are directly available from the libc.a or libc.so libraries and include the following APIs:

• MIPC

• IPC

• LAP

To add POSIX-like extended services, you must specify the required library in your Imakefile. These services include the following APIs:

• Blackbox

• SysEvent

• LDAP