Using the Solaris version of UNIX what is the role of shell? What are 3 features

Question

Using the Solaris version of UNIX what is the role of shell? What are 3 features and roles of each? Comments on security Comments on Administration Comments on networking Comments on performance Comments on programmability Other

Explanation / Answer

Standard shell on Solaris is POSIX shell which is a weaker shell then either ksh93 or bash. Default shell for Solaris is the "Bourne shell" or /usr/bin/sh It's a pretty weak outdated shell; nothing to speak about and the idea that it somehow increases the security of root due to the fact that it is static linked is one of Solaris urban myths (see Solaris Root Shell Mini-FAQ for details). It's actually pretty safe to replace it as a root shell. It might slightly increase the chances of recovery in case /usr partition is damaged, but this is a pretty serious case and usually means serious troubles with other partitions on the disk anyway (unless this is the case when link /bin -> usr/bin is destroyed, but such cases are simple to fight by refereeing shell as /use/bin/ksh in passwd). If this is a serious trouble then booting from a CD and mounting the damaged volume is always a good idea and in this case it does not matter what shell root is using; you can change it anyway. Solaris Posix shell is ksh88 plus some ksh93 enhancements and is not as powerful as ksh93. It's pretty stupid not to use ksh93 those days and here Sun developers should accpt the blame of being exremly stupid. Bash is also a good interactive shell, the first Bourne line shell that can compete on user-frendliness with tcsh. But it has GNU christnas tree problems (libraries this, libararies that). also you cannot use it as a role shell. Some interesting features of bash 3.0 include: ! history retrieval arrows keys history browsing Indexed arrays of unlimited size Integer arithmetic in any base from two to sixty-four shell debugger The command line editing capabilities of bash are very good. Bash allows to perform "bang commands" repeatedly, saving you a lot of typing (via the "! syntax). BASH 3.0 also introduced some important ksh93-style enhancements, for example it does has process substitution in pipes ( > (command) and < (command) ). Each command argument of the form (list) or =(list) is subject to process substitution. In the case of the forms, the shell will run process list asynchronously, connected to a named pipe (FIFO). The name of this pipe will become the argument to the command. If the form with > is selected then writing to this file will provide input for list. This also allows you to use the output of several commands simultaneously as input for another program. For instance you can compare the contents of two directories by typing:

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