Hello World Program In C

[WalidKhan]

I'm attempting to compile a hello world c programme on the mac terminal and getting the following errors:

mysource.c:1:19: error: /usr/local/include/stdio.h: Permission denied
mysource.c: In function ‘main’:
mysource.c:2: warning: incompatible implicit declaration of built-in function ‘printf’

This is what I typed into the terminal (the name of the.c file is mysource):

MacBook-Pro:~ drummer014$ gcc mysource.c -o mysource

I had xcode 3 installed and received the same error, then I installed xcode 4.2 today and am experiencing the same issue. I'm using a MacBook Pro running Snow Leopard. I have tried typing gcc and then dragging the file into the terminal after following this scaler guide, but I still get the same issue. Any assistance would be highly appreciated.

I used the command gcc —verbose mysource.c -o mysource. What I got was as follows:

Using built-in specs.
    Target: i686-apple-darwin10
    Configured with: /private/var/tmp/llvmgcc42/llvmgcc42-2336.1~3/src/configure --disable-         checking --enable-werror --prefix=/Developer/usr/llvm-gcc-4.2 --mandir=/share/man --enable-languages=c,objc,c++,obj-c++ --program-prefix=llvm- --program-transform-name=/^[cg][^.-]*$/s/$/-4.2/ --with-slibdir=/usr/lib --build=i686-apple-darwin10 --enable-         llvm=/private/var/tmp/llvmgcc42/llvmgcc42-2336.1~3/dst-llvmCore/Developer/usr/local --program-prefix=i686-apple-darwin10- --host=x86_64-apple-darwin10 --target=i686-apple-darwin10 --with-gxx-include-dir=/usr/include/c++/4.2.1
Thread model: posix
    gcc version 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.1.00)
     /usr/llvm-gcc-.2/bin/../libexec/gcc/i686-apple-darwin10/4.2.1/cc1 -quiet -v -imultilib    x86_64 -iprefix /usr/llvm-gcc-4.2/bin/../lib/gcc/i686-apple-darwin10/4.2.1/ -D__DYNAMIC__ mysource.c -fPIC -quiet -dumpbase mysource.c -mmacosx-version-min=10.6.8 -m64 -mtune=core2 -auxbase mysource -version -o /var/folders/7r/7rMZhHx3F0WhnoyEK1zUgE+++TI/-Tmp-//ccaqeJkd.s
ignoring nonexistent directory "/usr/llvm-gcc-4.2/bin/../lib/gcc/i686-apple-darwin10/4.2.1/../../../../i686-apple-darwin10/include"
ignoring nonexistent directory "/Developer/usr/llvm-gcc-4.2/lib/gcc/i686-apple-darwin10/4.2.1/../../../../i686-apple-darwin10/include"
    #include "..." search starts here:
    #include <...> search starts here:
     /usr/llvm-gcc-4.2/bin/../lib/gcc/i686-apple-darwin10/4.2.1/include
     /usr/local/include
     /Developer/usr/llvm-gcc-4.2/lib/gcc/i686-apple-darwin10/4.2.1/include
     /usr/include
     /System/Library/Frameworks (framework directory)
     /Library/Frameworks (framework directory)
    End of search list.
    GNU C version 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.1.00) (i686-apple-    darwin10)
    compiled by GNU C version 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.1.00).
    GGC heuristics: --param ggc-min-expand=150 --param ggc-min-heapsize=131072
    Compiler executable checksum: e787fa4ffdc9e78ad5e913828c220d85
    mysource.c:1:19: error: /usr/local/include/stdio.h: Permission denied
    mysource.c: In function ‘main’:
    mysource.c:3: warning: incompatible implicit declaration of built-in function ‘printf’

 

Edited March 30, 2023 by WalidKhan
spelling, code and url correction

[Sensei]

Open a normal terminal and use:

cat /usr/local/include/stdio.h

Does it work?

If you also have "Permission denied," open the terminal in administrator mode.

List contents of /usr/local and /usr/local/include to see if you have the right files there.

Finally, use the:

chmod -R 777 /usr/local/include/

-R should do it recursively with all files and subfolders.

(check the manual e.g. man chmod)

 

Before resolving the "Permission denied" error, there is no point in analyzing the rest of the messages..

 

You can use:

cd /usr/local

ls -l

or

cd /usr/local/include

ls -l

to see what permissions are assigned to files and folders.

chmod 777 filename means read+write+executable access for every administrator, user and guest (which is the weakest/dangerous one)

 

Refer to the manual:

https://man7.org/linux/man-pages/man1/chmod.1.html

 

Edited March 30, 2023 by Sensei