Thanks to everyone here... I am slowly able to realize the shell... I'm actually stuck at piping... I am able to handle a single pipe but how do I solve the problem of multiple pipes? I know it can be solved using recursion but some pseudo algorithm will be excellent... I don't understand how to actually use recursion here... I'm currently doing something like a parent creates two children and the first one executes one command and pipes it onto the second child which displays the output...
And when I used valgrind, to my surprise I found 15 memory leaks from the piping function that I wrote and I don't understand what could've gone wrong... My pseudo code looks something like this:
Am I doing something wrong?
Last edited by Legend986; 10-24-2007 at 02:45 AM..
if somebody can help me pls.
i need the source code for a shell which compiles C or java programs.
i need a very short and simple one, just for the compiling part, in UNIX
Respect (4 Replies)
#!/usr/bin/m4
when running m4 scripts with "#!/usr/bin/m4" they are executed properly, but "#!/usr/bin/m4" is printed out - how to avoid it?
Thanks in advance. (5 Replies)
Hello guys - do you have any sample program implementing UNIX commands in an interpreter with Java? I can look up the simple ones such "ls" etc and then write my own commands.
I would appreciate it. (2 Replies)
Hi,
I am writing a shell script that connects to a remote server and performs some tasks on the server and exits.
Since i am using a ssh connection, i am using a "expect" utility to supply the password automatically (which is present within the script).
In order to use this utility, i need to... (3 Replies)
Hi. My name is Caleb (a.k.a RagingNinja) form the whited00r forums. (Whited00r makes custom firmware for iOS devices).
I have been learning and creating simple shells scripts. I have been recently using VIM for Windows or using VirtualBox to run the UBUNTU OS within VirtualBox to create my shell... (2 Replies)
Hi,
Is it possible to choose the inerpreter conditionally.
For example, if whereis bash returns /usr/bin/bash then i need to choose #!/usr/bin/bash
else i need to use #!/usr/bin/sh.
Is it possible to achieve in a shell script?
Thanks (1 Reply)
Discussion started by: pandeesh
1 Replies
LEARN ABOUT HPUX
sh
sh(1) General Commands Manual sh(1)NAME
sh - overview of various system shells
SYNOPSIS
POSIX Shell
option] ... string] [arg ...]
option] ... string] [arg ...]
Korn Shell
option] ... string] [arg ...]
option] ... string] [arg ...]
C Shell
[command_file] [argument_list ...]
Key Shell
DESCRIPTION
Remarks
The POSIX .2 standard requires that, on a POSIX-compliant system, executing the command activates the POSIX shell (located in file on HP-UX
systems), and executing the command produces an on-line manual entry that displays the syntax of the POSIX shell command-line.
However, the command has historically been associated with the conventional Bourne shell, which could confuse some users. To meet stan-
dards requirements and also clarify the relationships of the various shells and where they reside on the system, this entry provides com-
mand-line syntax and a brief description of each shell, and lists the names of the manual entries where each shell is described in greater
detail.
The Bourne shell is removed from the system starting with HP-UX 11i Version 1.5. Please use the POSIX shell as an alternative.
Shell Descriptions
The HP-UX operating system supports the following shells:
POSIX-conforming command programming language and command interpreter
residing in file Can execute commands read from a terminal or a file. This shell conforms to current POSIX standards in
effect at the time the HP-UX system release was introduced, and is similar to the Korn shell in many respects. Similar in
many respects to the Korn shell, the POSIX shell contains a history mechanism, supports job control, and provides various
other useful features.
Korn-shell command programming language and commands interpreter
residing in file Can execute commands read from a terminal or a file. This shell, like the POSIX shell, contains a his-
tory mechanism, supports job control, and provides various other useful features.
A command language interpreter
that incorporates a command history buffer, C-language-like syntax, and job control facilities.
Restricted version of the POSIX shell command interpreter.
Sets up a login name and execution environment whose capabilities are more controlled (restricted) than normal user
shells.
restricted version of the Korn-shell command interpreter
Sets up a login name and execution environment whose capabilities are more controlled (restricted) than normal user
shells.
An extension of the standard Korn Shell
that uses hierarchical softkey menus and context-sensitive help.
+--------------+--------------------+
| To obtain: | Use the command: |
+--------------+--------------------+
| POSIX Shell | /usr/bin/sh ... |
| Korn Shell | /usr/bin/ksh ... |
| C Shell | /usr/bin/csh ... |
| Key Shell | /usr/bin/keysh |
+--------------+--------------------+
These shells can also be the default invocation, depending on the entry in the file. See also chsh(1).
WARNINGS
Many manual entries contain descriptions of shell behavior or describe program or application behavior similar to ``the shell'' with a ref-
erence to ``see sh(1)''.
SEE ALSO
For more information on the various individual shells, see:
keysh(1) Key Shell description.
ksh(1) Korn Shell description.
sh-posix(1) POSIX Shell description.
csh(1) C Shell description.
sh(1)