Aimed at larger systems. Devices are addressable to 21 bytes, files to 20 bytes. 128K memory (separate instruction and data space) is needed for some utilities.
Portability. Code of the operating system and most utilities has been extensively revised to minimize its dependence on particular hardware.
Fortran 77. F77 compiler for the new standard language is compatible with C at the object level. A Fortran structurer, STRUCT, converts old, ugly Fortran into RATFOR, a structured dialect usable with F77.
Shell. Completely new SH program supports string variables, trap handling, structured programming, user profiles, settable search path, multilevel file name generation, etc.
Document preparation. TROFF phototypesetter utility is standard. NROFF (for terminals) is now highly compatible with TROFF. MS macro package provides canned commands for many common formatting and layout situations. TBL provides an easy to learn language for preparing complicated tabular material. REFER fills in bibliographic citations from a data base.
UNIX-to-UNIX file copy. UUCP performs spooled file transfers between any two machines.
Data processing. SED stream editor does multiple editing functions in parallel on a data stream of indefinite length. AWK report generator does free-field pattern selection and arithmetic operations.
Program development. MAKE controls re-creation of complicated software, arranging for minimal recompilation.
Debugging. ADB does postmortem and breakpoint debugging, handles separate instruction and data spaces, floating point, etc.
C language. The language now supports definable data types, generalized initialization, block structure, long integers, unions, explicit type conversions. The LINT verifier does strong type checking and detection of probable errors and portability problems even across separately compiled functions.
Lexical analyzer generator. LEX converts specification of regular expressions and semantic actions into a recognizing subroutine. Analogous to YACC.
Graphics. Simple graph-drawing utility, graphic subroutines, and generalized plotting filters adapted to various devices are now standard.
Standard input-output package. Highly efficient buffered stream I/O is integrated with formatted input and output.
Other. The operating system and utilities have been enhanced and freed of restrictions in many other ways too numerous to relate.
The 7th edition UNIX operating system runs on a DEC PDP-11/45 or 11/70* with at least the following equipment:
The following equipment is strongly recommended:
The system is normally distributed on 9-track tape. The minimum memory and disk space specified is enough to run and maintain UNIX. More will be needed to keep all source on line, or to handle a large number of users, big data bases, diversified complements of devices, or large programs. The resident code occupies 12-20K words depending on configuration; system data occupies 10-28K words.
There is no commitment to provide 7th edition UNIX on PDP-11/34, 11/40 and 11/60 hardware.
Most of the programs available as UNIX commands are listed. Source code and printed manuals are distributed for all of the listed software except games. Almost all of the code is written in C. Commands are self-contained and do not require extra setup information, unless specifically noted as ``interactive.'' Interactive programs can be made to run from a prepared script simply by redirecting input. Most programs intended for interactive use (e.g., the editor) allow for an escape to command level (the Shell). Most file processing commands can also go from standard input to standard output (``filters''). The piping facility of the Shell may be used to connect such filters directly to the input or output of other programs.