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diff --git a/usr/src/lib/libshell/common/PROMO.mm b/usr/src/lib/libshell/common/PROMO.mm new file mode 100644 index 0000000000..332ff3a855 --- /dev/null +++ b/usr/src/lib/libshell/common/PROMO.mm @@ -0,0 +1,141 @@ +.H 1 ksh93 +KSH-93 is the most recent version of the KornShell Language +described in +"The KornShell Command and Programming Language," +by Morris Bolsky and David Korn of AT&T Bell Laboratories, ISBN 0-13-182700-6. +The KornShell is a shell programming language, +which is upward compatible with "sh" (the Bourne Shell), +and is intended to conform to the IEEE P1003.2/ISO 9945.2 Shell and +Utilities standard. +KSH-93 provides an enhanced programming environment in +addition to the major command-entry features of the BSD +shell "csh". With KSH-93, medium-sized programming tasks can be +performed at shell-level without a significant loss in performance. +In addition, "sh" scripts can be run on KSH-93 without modification. +.P +The code should conform to the IEEE POSIX 1003.1 standard and to the +proposed ANSI-C standard so that it should be portable to all +such systems. Like the previous version, KSH-88, +it is designed to accept eight bit character sets +transparently, thereby making it internationally compatible. +It can support multi-byte characters sets with some characteristics +of the character set given at run time. +.P +KSH-93 provides the following features, many of which were also inherent +in KSH-88: +.BL +.LI +Enhanced Command Re-entry Capability: The KSH-93 history +function records commands entered at any shell level and stores +them, up to a user-specified limit, even after you log off. +This allows you to re-enter long commands with a few keystrokes +- even those commands you entered yesterday. +The history file allows for eight bit characters in +commands and supports essentially unlimited size histories. +.LI +In-line Editing: In "sh", the only way to fix mistyped +commands is to backspace or retype the line. KSH-93 allows you +to edit a command line using a choice of EMACS-TC or "vi" +functions. +You can use the in-line editors to complete filenames as +you type them. +You may also use this editing feature when entering +command lines from your history file. +A user can capture keystrokes and rebind keys to customize the +editing interface. +.LI +Extended I/O Capabilities: KSH-93 provides several I/O +capabilities not available in "sh", including the ability to: +.BL +.LI +specify a file descriptor for input and output +.LI +start up and run co-processes +.LI +produce a prompt at the terminal before a read +.LI +easily format and interpret responses to a menu +.LI +echo lines exactly as output without escape processing +.LI +format output using printf formats. +.LI +read and echo lines ending in "\e". +.LE +.LI +Improved performance: KSH-93 executes many scripts faster +than the System V Bourne shell. A major reason for this is +that many of the standard utilities are built-in. +To reduce the time to initiate a command, KSH-93 allows +commands to be added as built-ins at run time +on systems that support dynamic loading such as System V Release 4. +.LI +Arithmetic: KSH-93 allows you to do integer arithmetic in any +base from two to sixty-four. You can also do double +precision floating point arithmetic. +Almost the complete set of C language operators are available +with the same syntax and precedence. +Arithmetic expressions can be used to as an argument expansion +or as a separate command. +In addition there is an arithmetic for command that works +like the for statement in C. +.LI +Arrays: KSH-93 supports both indexed and associative arrays. +The subscript for an indexed array is an arithmetic expression, +whereas, the subscript for an associative array is a string. +.LI +Shell Functions and Aliases: Two mechanisms - functions and +aliases - can be used to assign a user-selected identifier to +an existing command or shell script. +Functions allow local variables and provide scoping +for exception handling. +Functions can be searched for and loaded on first reference the +way scripts are. +.LI +Substring Capabilities: KSH-93 allows you to create a +substring of any given string either by specifying the starting +offset and length, or by stripping off leading +or trailing substrings during parameter substitution. +You can also specify attributes, such as upper and lower case, +field width, and justification to shell variables. +.LI +More pattern matching capabilities: KSH-93 allows you to specify +extended regular expressions for file and string matches. +.LI +KSH-93 uses a hierarchal name space for variables. +Compound variables can be defined and variables can +be passed by reference. In addition, each variable +can have one or more disciplines associated with +it to intercept assignments and references. +.LI +Improved debugging: KSH-93 can generate line numbers on execution +traces. Also, I/O redirections are now traced. +There is a DEBUG trap that gets evaluated after each command +so that errors can be localized. +.LI +Job Control: On systems that support job control, including +System V Release 4, KSH-93 +provides a job-control mechanism almost identical to that of +the BSD "csh", version 4.1. +This feature allows you +to stop and restart programs, and to move programs between the +foreground and the background. +.LI +Added security: +KSH-93 can execute scripts which do not have read permission +and scripts which have the setuid and/or setgid set when +invoked by name, rather than as an argument to the shell. +It is possible to log or control the execution of setuid and/or +setgid scripts. +The noclobber option prevents you from accidentally erasing +a file by redirecting to an existing file. +.LI +KSH-93 can be extended by adding built-in commands at run time. +In addition, KSH-93 can be used as a library that can +be embedded into an application to allow scripting. +.LE +Documentation for KSH-93 consists of an "Introduction to KSH-93", +"Compatibility with the Bourne Shell" and a manual page and a +README file. In addition, the "New KornShell Command and Programming +Language," book is available from Prentice Hall. + |