dyld troubleshoot for newer macs; addresses libcs50 issue 331

libraries/cs50/c.rst

@@ -12,14 +12,14 @@ Ubuntu
 -------
 
 .. code-block:: bash
-    
+
     $ curl -s https://packagecloud.io/install/repositories/cs50/repo/script.deb.sh | sudo bash
     $ sudo apt install libcs50
 
 
 Fedora
 -------
-.. code-block:: bash 
+.. code-block:: bash
 
         $ curl -s https://packagecloud.io/install/repositories/cs50/repo/script.rpm.sh | sudo bash
         $ dnf install libcs50
@@ -32,13 +32,15 @@ From Source (Linux and Mac)
   3. ``cd libcs50-*``
   4. ``sudo make install``
 
+By default, we install to ``/usr/local``. If you'd like to change the installation location, run ``sudo DESTDIR=/path/to/install make install`` instead.
+
 
 Environment Variables
 =====================
 
 For parity with `Visual Studio Code for CS50 </code/>`_ and `cli50 <cli50/>`_, you may want to set these environment variables:
 
-.. code-block:: bash 
+.. code-block:: bash
 
     CC="clang"
     CFLAGS="-ferror-limit=1 -gdwarf-4 -ggdb3 -O0 -std=c11 -Wall -Werror -Wextra -Wno-gnu-folding-constant -Wno-sign-compare -Wno-unused-parameter -Wno-unused-variable -Wno-unused-but-set-variable -Wshadow"
@@ -59,11 +61,11 @@ Alternatively, if using a ``Makefile`` to compile a program (e.g., ``foo``) from
 
     SRCS = foo.c bar.c
     OBJS = $(SRCS:.c=.o)
- 
- 
+
+
     $(EXE): $(OBJS)
 	 $(CC) $(CFLAGS) -o $@ $(OBJS) $(LDLIBS)
- 
+
 
 
 Usage
@@ -83,7 +85,7 @@ Usage
 
 
 .. function:: char get_char(const char *format, ...)
-    
+
     :param format: the :func:`printf`-like format string used to display the prompt
     :param ...: values to be substituted into the format string a la :func:`printf`
     :returns: the :code:`char` equivalent to the line read from stdin, or :macro:`CHAR_MAX` on error
@@ -92,7 +94,7 @@ Usage
     if text does not represent a single char, user is reprompted.
 
     Example usage::
-        
+
         #include <stdio.h>
         #include <cs50.h>
 
@@ -120,7 +122,7 @@ Usage
 
 
 .. function:: double get_double(const char *format, ...)
-    
+
     :param format: the :func:`printf`-like format string used to display the prompt
     :param ...: values to be substituted into the format string a la :func:`printf`
 
@@ -157,7 +159,7 @@ Usage
 
 
 .. function:: int get_int(const char *format, ...)
-    
+
     :param format: the :func:`printf`-like format string used to display the prompt
     :param ...: values to be substituted into the format string a la :func:`printf`
 
@@ -170,8 +172,8 @@ Usage
 
 
         #include <cs50.h>
-        
-        ... 
+
+        ...
 
         // Returns the sum of two ints read from stdin, or INT_MAX if there was an error.
         int add_ints(void)
@@ -197,7 +199,7 @@ Usage
 
 
 .. function:: float get_float(const char *format, ...)
-    
+
     :param format: the :func:`printf`-like format string used to display the prompt
     :param ...: values to be substituted into the format string a la :func:`printf`
 
@@ -233,7 +235,7 @@ Usage
 
 
 .. function:: long get_long(const char *format, ...)
-    
+
     :param format: the :func:`printf`-like format string used to display the prompt
     :param ...: values to be substituted into the format string a la :func:`printf`
 
@@ -245,8 +247,8 @@ Usage
 
 
         #include <cs50.h>
-        
-        ... 
+
+        ...
 
         // Returns the difference of two longs read from stdin, or LONG_MAX if there was an error.
         long subtract_longs(void)
@@ -312,9 +314,22 @@ If when compiling your program, you see:
 
     ``/usr/bin/ld: cannot find -lcs50``:
         Add ``export LIBRARY_PATH=/usr/local/lib`` to your ``.bashrc``.
-    
+
     ``fatal error: 'cs50.h' file not found``:
         Add ``export C_INCLUDE_PATH=/usr/local/include`` to your ``.bashrc``.
-    
+
     ``cannot open shared object file: No such file or directory``:
         Add ``export LD_LIBRARY_PATH=/usr/local/lib`` to your ``.bashrc``.
+
+
+If when executing your program, you see something similar to (the following error is especially prevalent on newer Macs):
+
+.. code-block:: bash
+
+    dyld[.....]: Library not loaded: libcs50-11.0.3.dylib
+      Referenced from: <.....> .....
+      Reason: tried: 'libcs50-11.0.3.dylib' (no such file), .....
+
+Add ``export DYLD_LIBRARY_PATH=/usr/local/lib`` to your ``.bashrc``.
+
+If you're not using Bash, use whatever command sets the value of environmental variables in your preferred shell. If you set ``DESTDIR`` to something other than ``/usr/local``, substitute it in for ``/usr/local`` in the suggestions above.