moved tables from unix programming interface book into its own directory

unix_programming_environment/awk_operators.txt

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+------------------ Table 4.4 ------------------
+ awk Operators (increasing order of precedence)
+
+= += -k *= /= %=        assignment; v op= expr is v = v op (expr)
+||                      OR: expr1 || expr2 true if either is;
+                            expr2 not evaluated if expr1 is true
+&&                      AND: expr1 && expr2 true if both are;
+                            expr2 not evaluated if expr1 is false
+!                       negate value of expression
+> >= < <= == != ~ !~    relational operators;
+                            ~ and !~ are match and non-match
+nothing                 string concatenation
++ -                     plus, minus
+* / %                   multiply, divide, remainder
+++ --                   increment, decrement (prefix or postfix)

unix_programming_environment/grep_egrep.txt

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+    ----------------- Table 4.1 -----------------
+     --- grep and egrep Regular Expressions ---
+          (decreasing order of precedence)
+
+c       any non-special character c matches itself
+\c      turn off any special meaning of character c
+^       beginning of line
+$       end of line
+.       any single character
+[...]   any one of characters in ...; ranges like a-z are legal
+[^...]  any single character not in ...; ranges are legal
+\n      what the n'th \(...\) matched (grep only)
+r*      zero or more occurrences of r
+r+      one or more occurrences of r (egrep only)
+r?      zero or one occurrences of r (egrep only)
+r1 r2   r1 followed by r2
+r1|r2   r1 or r2 (egrep only)
+\(r\)   tagged regular expression r (grep only); can be nested
+(r)     regular expression r (egrep only); can be nested
+
+        No regular expression matches a newline.
+

unix_programming_environment/sed.txt

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+----------------------------- Table 4.2 -----------------------------
+            Summary of sed Commands
+
+a\              append lines to output until one not ending in \
+b label         branch to command : label
+c\              change lines to following text as in a
+d               delete line; read next input line
+i\              insert following text before next output
+l               list line, making all non-printing characters visible
+p               print line
+q               quit
+r file          read file, copy contents to output
+s/old/new/f     substitute new for old. If f=g, replace all occurrences;
+                    f=p, print; f=w file, write to file
+t label         test: branch to label if substitution made to current line
+w file          write line to file
+y/str1/str2     replace each character from str1 with corresponding
+                    character from str2 (no ranges allowed)
+=               print current input line number
+!cmd            do sed cmd only if line is not selected
+: label         set label for b and t Commands
+{               treat commands up to matching } as a group