10-18-2007
Yeah sure... I might seem a little ambitious and I'm sure it'll take some time to build all that but I'll show it to you once I'm done with it... So do you have any suggestions to give me as far as my last post is concerned? I've just pasted the relevant matter here:
And while implementing pipes, when I issue a command such as "ls | grep .c" in my interpreter, after parsing it, what should I be doing? I read about file descriptors and am assuming the following has to be done:
1. Parse the command line
2. argv[0] contains ls, so fork a process and execute it but redirect the output to a file (I don't know how this can be done internally in the C Code. I know I need to use the execv command to execute but how will I redirect?)
3. In the next parse, I scan the "|" character and so I know that the user wants to pipe the output and at this stage I would fork another process with the argv[2] string i.e. "grep .c" (but this will be stored in argv[2] and argv[3]. How will I know that the second one has command line arguments too and how should I handle them?) and then direct the output of this to the stdout.
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