\documentclass[10pt,a4paper]{article}

% Packages
\usepackage{fancyhdr}           % For header and footer
\usepackage{multicol}           % Allows multicols in tables
\usepackage{tabularx}           % Intelligent column widths
\usepackage{tabulary}           % Used in header and footer
\usepackage{hhline}             % Border under tables
\usepackage{graphicx}           % For images
\usepackage{xcolor}             % For hex colours
%\usepackage[utf8x]{inputenc}    % For unicode character support
\usepackage[T1]{fontenc}        % Without this we get weird character replacements
\usepackage{colortbl}           % For coloured tables
\usepackage{setspace}           % For line height
\usepackage{lastpage}           % Needed for total page number
\usepackage{seqsplit}           % Splits long words.
%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
\usepackage[normalem]{ulem}     % For underlining links
% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
\usepackage{wasysym}            % Symbols
%\usepackage[english,german,french,spanish,italian]{babel}              % Languages

% Document Info
\author{Interesting}
\pdfinfo{
  /Title (c-file-handling.pdf)
  /Creator (Cheatography)
  /Author (Interesting)
  /Subject (C File Handling Cheat Sheet)
}

% Lengths and widths
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\addtolength{\hoffset}{-3cm}
\addtolength{\voffset}{-2cm}
\setlength{\tabcolsep}{0.2cm} % Space between columns
\setlength{\headsep}{-12pt} % Reduce space between header and content
\setlength{\headheight}{85pt} % If less, LaTeX automatically increases it
\renewcommand{\footrulewidth}{0pt} % Remove footer line
\renewcommand{\headrulewidth}{0pt} % Remove header line
\renewcommand{\seqinsert}{\ifmmode\allowbreak\else\-\fi} % Hyphens in seqsplit
% This two commands together give roughly
% the right line height in the tables
\renewcommand{\arraystretch}{1.3}
\onehalfspacing

% Commands
\newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour
\newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols
\newcolumntype{x}[1]{>{\raggedright}p{#1}} % New column types for ragged-right paragraph columns
\newcommand{\tn}{\tabularnewline} % Required as custom column type in use

% Font and Colours
\definecolor{HeadBackground}{HTML}{333333}
\definecolor{FootBackground}{HTML}{666666}
\definecolor{TextColor}{HTML}{333333}
\definecolor{DarkBackground}{HTML}{A3A3A3}
\definecolor{LightBackground}{HTML}{F3F3F3}
\renewcommand{\familydefault}{\sfdefault}
\color{TextColor}

% Header and Footer
\pagestyle{fancy}
\fancyhead{} % Set header to blank
\fancyfoot{} % Set footer to blank
\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
    }
\end{tabulary}
\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{C File Handling Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Interesting} via \textcolor{DarkBackground}{\uline{cheatography.com/202766/cs/43061/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}Interesting \\
  \uline{cheatography.com/interesting} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 16th April, 2024.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
  \SetRowColor{white}
  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
\raggedright
\raggedcolumns

% Set font size to small. Switch to any value
% from this page to resize cheat sheet text:
% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{3}

\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{File Functions}}  \tn
% Row 0
\SetRowColor{LightBackground}
int fscanf(FILE {\emph{stream, const char }}format, ...) & reads formatted input from a stream. \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
int fprintf(FILE {\emph{stream, const char }}format, ...) & sends formatted output to a stream. \tn 
% Row Count 6 (+ 3)
% Row 2
\SetRowColor{LightBackground}
FILE {\emph{fopen(const char }}filename, const char *mode) & opens the filename pointed to, by filename using the given mode. \{\{nl\}\}  	  "r"  Opens a file for reading. The file must exist. \{\{nl\}\} "w"  Creates an empty file for writing. If a file with the same name already exists, its content is erased and the file is considered as a new empty file. \{\{nl\}\}  	  "a"  Appends to a file. Writing operations, append data at the end of the file. The file is created if it does not exist. \tn 
% Row Count 28 (+ 22)
% Row 3
\SetRowColor{white}
int fseek(FILE *f, long int offset, int origin) & go forward offset times without reading the files\{\{nl\}\} origins: \{\{nl\}\} SEEK\_SET - from start of file \{\{nl\}\} SEEK\_END - end of file \{\{nl\}\} SEEK\_CUR - move from current location \tn 
% Row Count 37 (+ 9)
\end{tabularx}
\par\addvspace{1.3em}

\vfill
\columnbreak
\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{File Functions (cont)}}  \tn
% Row 4
\SetRowColor{LightBackground}
int ftell(FILE *f) & returns the distance from cursor to start of file \tn 
% Row Count 3 (+ 3)
% Row 5
\SetRowColor{white}
void rewind(FILE *f) & go back to start of file \tn 
% Row Count 5 (+ 2)
% Row 6
\SetRowColor{LightBackground}
int ferror(FILE *F) & returns 0 if no errors occured \tn 
% Row Count 7 (+ 2)
% Row 7
\SetRowColor{white}
fclose(FILE* F) & closes the file \tn 
% Row Count 8 (+ 1)
% Row 8
\SetRowColor{LightBackground}
size\_t fread(void {\emph{ptr, size\_t size, size\_t nmemb, FILE }}stream) & reads data from the given stream into the array pointed to, by ptr. \tn 
% Row Count 12 (+ 4)
% Row 9
\SetRowColor{white}
int fgetc(FILE *stream) & Gets the next character (an unsigned char) from the specified stream and advances the position indicator for the stream. \tn 
% Row Count 18 (+ 6)
% Row 10
\SetRowColor{LightBackground}
char {\emph{fgets(char }}str, int n, FILE *stream) & read line to str. stop when newline or eof is read \tn 
% Row Count 21 (+ 3)
% Row 11
\SetRowColor{white}
int fputc(int char, FILE *stream) & Writes a character specified by the argument char to the specified stream and advances the position indicator for the stream. \tn 
% Row Count 28 (+ 7)
% Row 12
\SetRowColor{LightBackground}
int fputs(const char {\emph{str, FILE }}stream) & Writes a string to the specified stream up to but not including the null character. \tn 
% Row Count 33 (+ 5)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Reading and writing binary files}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{\#include \textless{}stdio.h\textgreater{} \newline \#define SIZE 20 \newline struct Person\{ \newline char name{[}SIZE{]}; \newline long id; \newline float age; \newline \} typedef person\_t; \newline  \newline void main()\{ \newline person\_t p1=\{"momo", 1111, 23.5\}, p2 = \{"gogo", 2222, 24.8\}, p3, p4; \newline  \newline FILE* f = fopen("persons.bin", "wb"); \newline  \newline fwrite(\&p1, sizeof(person\_t), 1, f); \newline fwrite(\&p2, sizeof(person\_t), 1, f); \newline  \newline fclose(f); \newline  \newline f = fopen("persons.bin", "rb"); \newline fread(\&p3, sizeof(person\_t), 1, f); \newline fread(\&p4, sizeof(person\_t), 1, f); \newline  \newline fclose(f); \newline  \newline printf("p3: name: \%s\textbackslash{}t id: \%ld\textbackslash{}t age: \%.2f\textbackslash{}n", p3.name, p3.id, p3.age); \newline printf("p4: name: \%s\textbackslash{}t id: \%ld\textbackslash{}t age: \%.2f\textbackslash{}n", p4.name, p4.id, p4.age); \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Reading file into struct}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{typedef struct person \{ \newline     char name{[}20{]}; \newline     int age; \newline \} person; \newline  \newline int main() \{ \newline     person {\emph{people = NULL; \newline     char name{[}20{]}; \newline     int size, age = 0; \newline     FILE }}f = fopen("people.txt", "r"); \newline     while (!feof(f))\{ \newline         scanf("\%s \%d", name, \&age); \newline         people = realloc(people, sizeof(person){\emph{(++age)}}size); \newline         strcpy((people+size-1)-\textgreater{}name, name); \newline         (people+size-1)-\textgreater{}age = age; \newline     \} \newline     fclose(f); \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{assume people.txt is formatted like this: \newline name1 age \newline name2 age}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Writing to file}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{\#include \textless{}stdio.h\textgreater{} \newline  \newline void main() \newline \{ \newline FILE* f = fopen("myFile.txt", "w"); \newline int res; \newline  \newline if (f == NULL)\{ \newline printf("Failed opening the file. Exiting!\textbackslash{}n"); \newline return; \newline \} \newline fputs("Hello World!\textbackslash{}n", f); \newline fclose(f); \newline  \newline f = fopen("myFile.txt", "a"); \newline fputs("And Good Morning!\textbackslash{}n", f); \newline fclose(f); \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}