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Re: Fist steps in compiling, gcc commands confusion

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On 21/04/2015 16:18, Alla _ wrote:
> Hello!
>
> Different resources advice different commands to compile a file:
>
> 1) gcc sample.c sample
>
> 2) gcc sample.c -o sample
>
> 3) gcc -o sample.c
>
> What are the difference in the meaning? What does -o stand for?
>
> The only command that produced results for me was gcc sample.c -o sample

I don't understand what (1) and (3) do.

  gcc sample.c -o sample

compiles "sample.c" into an object code (I think "sample.o") and links 
that into the executable file "sample", which you then have to run using:

./sample

gcc sample.c

compiles "sample.c" into an object file "sample.c", and then links that 
into the executable file "a.out" (don't ask why), which you have to run 
using:

./a.out

gcc -c sample.c

compiles "sample.c" into an object file "sample.c" only; it doesn't 
create an executable.

Summary:

* Every .c input file is compiled into a corresponding .o file.

* gcc will always link all input files (.c or already-compiled .o) into 
an executable unless -c is used.

* gcc will always name the executable "a.out" unless -o is used.

That's about the extent of my knowledge of gcc.

-- 
Bartc

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Fist steps in compiling, gcc commands confusion Alla _ <modelling.data@gmail.com> - 2015-04-21 08:18 -0700
  Re: Fist steps in compiling, gcc commands confusion Alla _ <modelling.data@gmail.com> - 2015-04-21 08:25 -0700
    Re: Fist steps in compiling, gcc commands confusion Morris Dovey <mrdovey@iedu.com> - 2015-04-21 10:56 -0500
      Re: Fist steps in compiling, gcc commands confusion David Brown <david.brown@hesbynett.no> - 2015-04-22 09:35 +0200
        Re: Fist steps in compiling, gcc commands confusion James Kuyper <jameskuyper@verizon.net> - 2015-04-22 11:15 -0400
          Re: Fist steps in compiling, gcc commands confusion David Brown <david.brown@hesbynett.no> - 2015-04-23 01:31 +0200
        Re: Fist steps in compiling, gcc commands confusion Keith Thompson <kst-u@mib.org> - 2015-04-22 08:43 -0700
          Re: Fist steps in compiling, gcc commands confusion Bartc <bc@freeuk.com> - 2015-04-22 18:57 +0100
            Re: Fist steps in compiling, gcc commands confusion Keith Thompson <kst-u@mib.org> - 2015-04-22 11:35 -0700
  Re: Fist steps in compiling, gcc commands confusion James Kuyper <jameskuyper@verizon.net> - 2015-04-21 12:01 -0400
  Re: Fist steps in compiling, gcc commands confusion John Gordon <gordon@panix.com> - 2015-04-21 16:01 +0000
    Re: Fist steps in compiling, gcc commands confusion Tim Prince <tprince@computer.org> - 2015-04-21 13:11 -0400
    Re: Fist steps in compiling, gcc commands confusion Keith Thompson <kst-u@mib.org> - 2015-04-21 12:09 -0700
  Re: Fist steps in compiling, gcc commands confusion Bartc <bc@freeuk.com> - 2015-04-21 18:25 +0100
    Re: Fist steps in compiling, gcc commands confusion Keith Thompson <kst-u@mib.org> - 2015-04-21 12:11 -0700
  Re: Fist steps in compiling, gcc commands confusion Keith Thompson <kst-u@mib.org> - 2015-04-21 11:16 -0700

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