diff --git a/base/mp_replace.sas b/base/mp_replace.sas
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+/**
+  @file
+  @brief Performs a text substitution on a file
+  @details Reads a file in byte by byte, performing text substiution where a
+  match is found.
+
+  This macro can be used on files where lines are longer than 32767.
+
+  If you are running a version of SAS that will allow the io package in LUA, you
+  can also use this macro: mp_gsubfile.sas
+
+  Usage:
+
+      %let file=%sysfunc(pathname(work))/file.txt;
+      %let str=replace/me;
+      %let rep=with/this;
+      data _null_;
+        file "&file";
+        put 'blahblah';
+        put "blahblah&str.blah";
+        put 'blahblahblah';
+      run;
+      %mp_replace(file=&file, patternvar=str, replacevar=rep)
+      data _null_;
+        infile "&file";
+        input;
+        list;
+      run;
+
+  @param file= (0) The file to perform the substitution on
+  @param patternvar= Macro variable NAME containing the string to search for
+  @param replacevar= Macro variable NAME containing the replacement string
+  @param outfile= (mp_rplce) The output fileref to contain the adjusted file.
+
+  <h4> SAS Macros </h4>
+  @li ml_gsubfile.sas
+
+  <h4> Related Macros </h4>
+  @li mp_gsubfile.test.sas
+
+  @version 9.4
+  @author Allan Bowe
+**/
+
+%macro mp_replace(file=0,
+  patternvar=,
+  replacevar=,
+  outref=mp_rplce
+)/*/STORE SOURCE*/;
+
+  %ml_gsubfile()
+
+%mend mp_replace;