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Diffstat (limited to 'usr/src/lib/libshell/common/COMPATIBILITY')
| -rw-r--r-- | usr/src/lib/libshell/common/COMPATIBILITY | 134 |
1 files changed, 0 insertions, 134 deletions
diff --git a/usr/src/lib/libshell/common/COMPATIBILITY b/usr/src/lib/libshell/common/COMPATIBILITY deleted file mode 100644 index d4d645a99a..0000000000 --- a/usr/src/lib/libshell/common/COMPATIBILITY +++ /dev/null @@ -1,134 +0,0 @@ - - KSH-93 VS. KSH-88 - - -The following is a list of known incompatibilities between ksh-93 and ksh-88. -I have not include cases that are clearly bugs in ksh-88. I also have -omitted features that are completely upward compatible. - -1. Functions, defined with name() with ksh-93 are compatible with - the POSIX standard, not with ksh-88. No local variables are - permitted, and there is no separate scope. Functions defined - with the function name syntax, maintain compatibility. - This also affects function traces. - -2. ! is now a reserved word. As a result, any command by that - name will no longer work with ksh-93. - -3. The -x attribute of alias and typeset -f is no longer - effective and the ENV file is only read for interactive - shells. You need to use FPATH to make function definitions - visible to scripts. - -4. A built-in command named command has been added which is - always found before the PATH search. Any script which uses - this name as the name of a command (or function) will not - be compatible. - -5. The output format for some built-ins has changed. In particular - the output format for set, typeset and alias now have single - quotes around values that have special characters. The output - for trap without arguments has a format that can be used as input. - -6. With ksh-88, a dollar sign ($') followed by a single quote was - interpreted literally. Now it is an ANSI-C string. You - must quote the dollar sign to get the previous behavior. - Also, a $ in front of a " indicates that the string needs - to be translated for locales other than C or POSIX. The $ - is ignored in the C and POSIX locale. - -7. With ksh-88, tilde expansion did not take place inside ${...}. - with ksh-93, ${foo-~} will cause tilde expansion if foo is - not set. You need to escape the ~ for the previous behavior. - -8. Some changes in the tokenizing rules where made that might - cause some scripts with previously ambiguous use of quoting - to produce syntax errors. - -9. Programs that rely on specific exit values for the shell, - (rather than 0 or non-zero) may not be compatible. The - exit status for many shell failures has been changed. - -10. Built-ins in ksh-88 were always executed before looking for - the command in the PATH variable. This is no longer true. - Thus, with ksh-93, if you have the current directory first - in your PATH, and you have a program named test in your - directory, it will be executed when you type test; the - built-in version will be run at the point /bin is found - in your PATH. - -11. Some undocumented combinations of argument passing to ksh - builtins no longer works since ksh-93 is getopts conforming - with respect to its built-ins. For example, typeset -8i - previously would work as a synonym for typeset -i8. - -12. Command substitution and arithmetic expansion are now performed - on PS1, PS3, and ENV when they are expanded. Thus, ` and $( - as part of the value of these variables must be preceded by a \ - to preserve their previous behavior. - -13. The ERRNO variable has been dropped. - -14. If the file name following a redirection symbol contain pattern - characters they will only be expanded for interactive shells. - -15. The arguments to a dot script will be restored when it completes. - -16. The list of tracked aliases is not displayed with alias unless - the -t option is specified. - -17. The POSIX standard requires that test "$arg" have exit status - of 0, if and only if $arg is null. However, since this breaks - programs that use test -t, ksh93 treats an explicit test -t - as if the user had entered test -t 1. - -18. The ^T directive of emacs mode has been changed to work the - way it does in gnu-emacs. - -19. ksh-88 allowed unbalanced parenthes within ${name op val} whereas - ksh-93 does not. Thus, ${foo-(} needs to be written as ${foo-\(} - which works with both versions. - -20. kill -l in ksh-93 lists only the signal names, not their numerical - values. - -21. Local variables defined by typeset are statically scoped in - ksh93. In ksh88 they were dynamically scoped although this - behavior was never documented. - -22. The value of the variable given to getopts is set to ? when - the end-of-options is reached to conform to the POSIX standard. - -23. Since the POSIX standard requires that octal constants be - recongnized, doing arithmetic on typeset -Z variables can - yield different results that with ksh88. Most of these - differences were eliminated in ksh93o. - -24. Starting after ksh93l, If you run ksh name, where name does - not contain a /, the current directory will be searched - before doing a path search on name as required by the POSIX - shell standard. - -25. In ksh93, cd - will output the directory that it changes - to on standard output as required by X/Open. With ksh88, - this only happened for interactive shells. - -26. As an undocumented feature of ksh-88, a leading 0 to an - assignment of an integer variable caused that variable - to be treated as unsigned. This behavior was removed - starting in ksh93p. - -27. The getopts builtin in ksh93 requires that optstring contain - a leading + to allow options to begin with a +. - -28. In emacs/gmacs mode, control-v will not display the version when - the stty lnext character is set to control-v or is unset. - The sequence escape control-v will display the shell version. - -29. In ksh88, DEBUG traps were executed. after each command. In ksh93 - DEBUG traps are exeucted before each command. - -30. In ksh88, a redirection to a file name given by an empty string was - ignored. In ksh93, this is an error. -I am interested in expanding this list so please let me know if you -uncover any others. |