How can I make GCC output not executable? - linux

I'm on Ubuntu and a certain .so file generated is executable. When I hit tab to autocomplete I get "something.so main.executable" instead of just "main.executable" which is a bit of an annoyance.
Is there a flag to pass to the linker to avoid the chmod or do I have to manually chmod -x after the fact?

Related

softlink to binary always use home folder path (instead of current folder)

kdevelop provides this AppImage binary:
wget -O KDevelop.AppImage https://download.kde.org/stable/kdevelop/5.1.1/bin/linux/KDevelop-5.1.1-x86_64.AppImage
chmod +x KDevelop.AppImage
./KDevelop.AppImage
It works well. So I want to make a soft link called kd to that binary in /usr/bin, eg:
/usr/bin/sudo ln -s KDevelop-5.1.1-x86_64.AppImage kd
Now if I run kd file1, I'd expect that it would open a file name file1 in the current folder, but it always tries to open a file name file1 in my home folder - which is not where it should be.
Is there some way to fix this issue?
Some possible causes:
The application always assumes that you want to open files in your home directory, effectively or literally prepending $HOME to the path. This would be a bug in any *nix program, and should be reported.
The application behaves differently when $(basename "$0") is not KDevelop.AppImage (what #Scheff said).
You are actually running a different kd.
Possible workarounds/investigations:
Pass the full path to the file on the command line. If it tries to open /home/you//full/path/you/provided it is obviously buggy, and you have a test case. If it does not, then there might be some gotcha to what your $PWD actually is. Try checking its value before running.
Symlink with the same name, using sudo ln -s KDevelop-5.1.1-x86_64.AppImage /usr/bin, and try running that. If it behaves the same, you've at least proven that the symlink is not the problem.
Run type -a kd and verify that your /usr/bin/kd comes up first. If not there might be an alias or shell built-in which takes precedence.
That said, what is the actual error message?

gcc is not using /tmp for temporary files

I am using Ubuntu Linux.
gcc is not using /tmp for temporary files (.i, .o, .s).
I exported environment variable TMPDIR like this:
export TMPDIR=/tmp
however gcc still tries to create tmp files in ./
so, if there is no W permission, gcc fails.
So I want to fix the gcc temporary file path to /tmp/
however, gcc is ignoring the TMPDIR.
What would be the problem here?
Adding the:
export TMPDIR=$HOME/temp;
line to ~/.profile file and then running:
. ~/.profile
command followed by a system restart did the trick for me in case anyone comes across this.

how to run gcc command in script to exe main.c

I'm new in linux trying to run .C program from another directory in script. script is in home directory and .C program is in Desktop directory. here is script.
#!/bin/bash
chmod 777 myscript
cd /home/unifi-007/Desktop/
gcc main -o main.c
./main
But i'm not getting it right. how to execute main.c in script.
The usage of gcc is clearly wrong, it should be gcc -o main main.c.
BTW, .C is a suffix for C++ (at least for GCC it is), not C.
BTW again, normally, you do not run a C source file, you compile it, and run the executable file generated by compiler (by linker, actually).

Update include path in linux

I have few header files in /my/path/to/file folder. I know how to include these files in new C program but everytime I need to type full path to header file before including it. Can I set some path variable in linux such that it automatically looks for header files ?
You could create a makefile. A minimal example would be:
INC_PATH=/my/path/to/file
CFLAGS=-I$(INC_PATH)
all:
gcc $(CFLAGS) -o prog src1.c src2.c
From here you could improve this makefile in many ways. The most important, probably, would be to state compilation dependencies (so only modified files are recompiled).
As a reference, here you have a link to the GNU make documentation.
If you do not want to use makefiles, you can always set an environment variable to make it easier to type the compilation command:
export MY_INC_PATH=/my/path/to/file
Then you could compile your program like:
gcc -I${MY_INC_PATH} -o prog src1.c src2.c ...
You may want to define MY_INC_PATH variable in the file .bashrc, or probably better, create a file in a handy place containing the variable definition. Then, you could use source to set that variable in the current shell:
source env.sh
I think, however, that using a makefile is a much preferable approach.
there is a similar question and likely better solved (if you are interested in a permanent solution): https://stackoverflow.com/a/558819/1408096
Try setting C_INCLUDE_PATH (for C header files) or CPLUS_INCLUDE_PATH (for C++ header files).
Kudos:jcrossley3
I'm not in Linux right now and I can't be bothered to reboot to check if everything's right, but have you tried making symbolic links? For example, if you are on Ubuntu:
$ cd /usr/include
$ sudo ln -s /my/path/to/file mystuff
So then when you want to include stuf, you can use:
#include <mystuff/SpamFlavours.h>

How can I prevent finding executable on $PATH?

I am using a system with an incomplete installation of GNAT, the GNU Ada compiler. A script (in the gdb testsuite) is finding /usr/bin/gnatmake and assumes that it can run Ada compiles. These fail because a the linker can't find libgnat.so.
I don't have root access, so I can't install libgnat.so or remove /usr/bin/gnatmake.
Is there any way to prevent a script from finding gnatmake in /usr/bin? I clearly cannot remove /usr/bin from the path.
Can you install a private, working version of gnatmake?
If you can, then you can create a symlink to the working version of gnatmake in your $HOME/bin directory:
ln -s /path/to/real/gnatmake ~/bin/gnatmake
Then insert your own $HOME/bin directory into your $PATH:
export PATH="$HOME/bin:$PATH"
Now the shell will find your version of gnatmake before the one in /usr/bin.
Try sudoing the script as yourself (sudo -u you ./script). In case you're not allow to sudo, you can also try exec VAR=val ./script. A third way would be to add another directory to $PATH with 'fake' empty scripts to shadow the ADA files.

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