heredoc

I was playing around with Python's subprocess module, trying a few examples but I can't seem to get heredoc statements to work. Here is the trivial example I was playing with: import subprocess a = "A String of Text" p = subprocess.Popen(["cat", "<<DATA\n" + a + "\nDATA"]) I get the following error when I run the code above: cat: <<DATA\nA String of Text\nDATA: No such file or directory Am I doing it wrong? Is this even possible? If so how would I go about doing it? Update Just wanted to say that this should never be performed in a real python program because there are better ways of doing

print <<EOF stuff EOF ; print <<EOF; stuff EOF Why would you use one over the other? Those two examples amount to the same thing behaviourally, but consider if you wanted to do something else after printing that block: print <<EOF stuff EOF . "more text here"; ...or maybe you need to test the result of the operation: print $unstable_filehandle <<EOF stuff EOF or warn "That filehandle finally disappeared: $!"; These examples are contrived, but you can see how sometimes it can be useful to be flexible about what code comes after the block of text. As tchrist points out, one thing that most

I have recently been doing fair amount of work in python and would like to be able to use its features instead of shell/bash builtins / shell scripting. So for a shell pipeline like this: echo -e "Line One\nLine Two\nLine Three" | (cat<<-HERE | python import sys print 'stdout hi' for line in sys.stdin.readlines(): print ('stdout hi on line: %s\n' %line) HERE ) | tee -a tee.out All that is printed is "stdout hi" What needs to be fixed here? thanks! TrueY It would be better if you explained what your goal is with this construction. Maybe it could be simplified? The problem is with this script

Can someone here explore the intricacies of using heredoc in PHP using example php code snippets? , based on what the manual says below? php.net manual says: It is very important to note that the line with the closing identifier must contain no other characters, except possibly a semicolon ( ; ). That means especially that the identifier may not be indented, and there may not be any spaces or tabs before or after the semicolon. It's also important to realize that the first character before the closing identifier must be a newline as defined by the local operating system. This is \n on UNIX

Is it possible to write a heredoc within another heredoc ? ssh -T -q yxz@server1 <<-"END_TEXT" . . ssh -T -q abc@server2 <<-"SUB_TEXT" . . SUB_TEXT . . END_TEXT Yes However, the nested heredoc terminator will only be recognized when indented if the indentation is done with actual tabs. Spaces won't work. So you probably want to do something more like: ssh s1 << \eof1 ssh s2 << \eof2 hostname eof2 eof1 来源： https://stackoverflow.com/questions/13254077/is-nesting-of-here-document-possible-in-a-unix-bash-script

I am trying to write a method in Ruby that uses a here-document of HTML code with input variables and fills them in accordingly. My method is: calcForm(left, op, right, result) The html tags I am using are <input type="text" name="left" value="?????"> <select name="op"> <option value="add" ?????>+</option> <option value="mul" ?????>*</option> </select> <input type="text" name="right" value="?????"> = ????? Everywhere there are question marks my method has to fill in with variables left, op, right, and result. For example, calcForm(6, "mul", 7, 42) should return the string: <input type="text"

If I have a method def some_method p = {} string = <<-MY_TERMINATOR Example text blah blah lorem ipsum something or another MY_TERMINATOR end how can I access the variable p[:name] from within the heredoc? You can interpolate just like in normal strings <<-TERMINATOR Example #{p[:name]} blah blah blah TERMINATOR 来源： https://stackoverflow.com/questions/3332849/can-i-access-a-variable-within-a-heredoc-in-ruby