Add a comment to an eps file created with saveas

I have many scripts that read my data, plot it, and save the figure as an encapsulated postscript file (used to use export_fig from the file exchange, now am using saveas). Sometimes I want to recreate a figure, and have to figure out which script generated it. Is there a way for my script to programmatically add a comment to the preamble of the postscript file so I can leave myself clues for recreating it? The head of my .eps file looks like this:

%!PS-Adobe-3.0 EPSF-3.0
%%Creator: (MATLAB, The Mathworks, Inc. Version 9.6.0.1072779 \(R2019a\). Operating System: Linux)
%%Title: /home/etownsen/quantumplasmonics/Record/Disorder/2QE1by12w6/EnergyInitBasis2872QEsNotResw1stPl1by12w6Coul1tb-1EQE112EQE212ydHndCDa0.01Db0.3Lhop0.2Seed4.eps
%%CreationDate: 2021-03-10T10:44:35
%%Pages: (atend)
%%BoundingBox:    85    28   861   514
%%LanguageLevel: 3
%%EndComments

So it seems likely that adding info to the "Creator" line would not hurt the eps file, and probably I can even safely add a line like

 %%Script: /here/something.m

Ideally it gets written when I create the file, but it might also be okay to add it after creating. I'd like the comment to contain the name (and path) of the script that created the eps. (And maybe the line number? but that's getting greedy.)

[Emily]

I haven't been able to do this when originally saving the file, but do have a code that edits the header after saving. Thanks to Kelly Kearney for this answer which helped me create it.

function f = EditEPSHeader(FigFile,string)
   % This function edits an eps file, [FigFile] to include [string] in the line of the header that contains "creator".
   % Use LineNumInfo = dbstack; LineNum = LineNumInfo.line; and ThisScript = mfilename('fullpath'); to generate string.
   % Emily Townsend November 2021


    Key   = '%%Creator:';

    %% 
    % Read entire file as character array
    FileContents = fileread(FigFile);
    % Split into lines
    FileContents = regexp(FileContents, '\r\n', 'split');
    % Find lines starting with certain letters
    istarget = startsWith(FileContents, Key) | ...
               contains(FileContents, 'Creator');

    % Replace lines that contain creator to include script name
    for ii = find(istarget)
        %FileContents{ii} = sprintf('%s : %s Line %d',FileContents{ii}, ThisScript, LineNum.line);
        FileContents{ii} = sprintf('%s : %s',FileContents{ii}, string);
    end
    % Write to new file
    fid = fopen(FigFile, 'wt');
    fprintf(fid, '%s\n', FileContents{:});
    fclose(fid);
    f = sprintf('%s edited to include %s',FigFile, string);
end

Called with:

% TestEditEPSHeaderFunction.m
% This code plots something, saves it as eps, then edits the eps file to
% include the name of this code.


x = 1:200;
y = x.^2;

FH = figure;
plot(y,x,'o:');
title('a plot');
FigFile = 'TestFig.eps'
saveas(FH,FigFile,'epsc');
LineNum = dbstack;
ThisScript = mfilename('fullpath')
string = sprintf('%s Line %d', ThisScript, LineNum.line - 1);

f=EditEPSHeader(FigFile,string)

[Emily]

This solution works on the windows machine. On the linux machine splitting into lines is accomplished by

 FileContents = regexp(FileContents, '\n', 'split');
 

(the search term is just '\n' rather than '\r\n'.)