Berkeley CSUA MOTD:Entry 31028
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2004/6/27 [Computer/SW/Languages/Perl, Computer/SW/Unix] UID:31028 Activity:nil
6/27    Stupid UNIX question: In a shell program, how do I read in
        standard input?  I want the program to take standard input
        and manipulate it in some way and then output the result to
        a file.  Once I have the program written, I know how to invoke
        it, but how do I, within the program, tell it to work with the
        standard input?
        \_ Read from fd 1:
           while read LINE ; do echo $LINE ; done <&1
        \_ If you just want to pass stdin through various external commands,
           it's easy; just run them, and the first one will consume stdin if
           it needs it; e.g.:
               #!/bin/sh
               awk '{print $2}' | sed 's/a/b/g' > file
           will "just work".  If you want to perform actual line by line
           shell script programming, you'll have to do like the previous post
           says.  But really, if you're doing actual custom programming of
           this type (i.e. not lots of external program invocations), you
           almost certainly are better off using perl or <insert favorite
           text munging language here> --dbushong
ERROR, url_link recursive (eces.Colorado.EDU/secure/mindterm2) 2025/07/08 [General] UID:1000 Activity:popular
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