Commands using gcc (17)

  • Try modifying the numbers in the "(i*(i>>8|i>>9)&46&i>>8))^(i&i>>13|i>>6)" part. Crudely stolen from http://www.xkcdb.com/9067


    10
    echo "main(i){for(i=0;;i++)putchar(((i*(i>>8|i>>9)&46&i>>8))^(i&i>>13|i>>6));}" | gcc -x c - && ./a.out | aplay
    SNDR · 2013-02-17 21:31:04 2

  • 8
    gcc -dM -E - < /dev/null
    ohe · 2009-10-28 14:13:19 1
  • outputs a f=220Hz guitar string sound (fifth string A) needs ALSA


    7
    f=220;echo "int s=16e3/$f;main(i){unsigned char v[s];read(0,v,s);for(;;)putchar(v[i%s]=(v[i%s]+v[++i%s])/2);}"|gcc -x c -&&./a.out</dev/urandom|aplay -d 2
    tehdog · 2013-06-28 14:52:53 3
  • /lib/ld-linux.so.2 is the runtime linker/loader for ELF binaries on Linux. =(cmd) is a zsh trick to take the output for the command "inside" it and save it to a temporary file. echo -e 'blah' | gcc -x c -o /dev/stdout - pipes the C source to gcc. -x c tells gcc that it's compiling C (which is required if it's reading from a pipe). -o /dev/stdout - tells it to write the binary to standard output and read the source from standard input. because of the the =() thing, the compiled output is stashed in a tempfile, which the loader then runs and executes, and the shell tosses the tempfile away immediately after running it. Show Sample Output


    6
    /lib/ld-linux.so.2 =(echo -e '#include <stdio.h>\nint main(){printf("c one liners\\n");}' | gcc -x c -o /dev/stdout -)
    mrtheplague · 2009-02-20 06:06:29 3
  • doesn't need /dev/null Show Sample Output


    4
    gcc -dM -E - <<<''
    bucciarati · 2009-10-28 14:26:56 0
  • Lists all macros and their values defined by gcc. Show Sample Output


    3
    gcc -dM -E - </dev/null
    slower · 2013-09-30 15:08:34 0

  • 2
    gcc -dM -E - < /dev/null
    lucasrangit · 2012-04-27 17:37:50 0
  • another one


    0
    echo | gcc -dM -E -
    Byung · 2011-05-09 09:59:24 0

  • 0
    for c in gcc bison dialog bc asdf; do if ! which $c >/dev/null; then echo Required program $c is missing ; exit 1; fi; done
    Mozai · 2011-06-27 12:54:02 0

  • 0
    gcc -E code.c | sed '/^\#/d' | indent -st -i2 > code-x.c
    enikulenkov · 2012-06-18 22:20:33 0
  • Something I pulled off 4chan, it plays a tune.


    0
    echo "main(i){for(i=0;;i++)putchar(((i*(i>>8|i>>9)&46&i >>8))^(i&i>>13|i>>6));}" | gcc -x c - && ./a.out | aplay
    r0nd0n · 2013-01-09 21:48:23 0
  • Install Ksuperkey one command in Kubuntu. You must manually add ksuperkey to autostart in System Settings KDE.


    0
    sudo apt-get install git gcc make libx11-dev libxtst-dev pkg-config -y && git clone https://github.com/hanschen/ksuperkey.git && cd ksuperkey && make && sudo mv ksuperkey /usr/bin/ksuperkey && cd ~ && rm -rf ksuperkey
    FadeMind · 2013-04-17 07:12:46 0

  • 0
    vim test.c && gcc -x c -o a.out test.c && ./a.out && rm a.out test.c
    ari2015 · 2013-09-08 15:09:09 0
  • This is a quick hack to make a gcc caller. Since it runs with gcc instead of tcc, it's a bit more trustworthy as far as the final answers of things go. Show Sample Output


    -3
    alias cstdin='echo "Ctrl-D when done." && gcc -Wall -o ~/.stdin.exe ~/.stdin.c && ~/.stdin.exe'
    taliver · 2009-11-19 16:38:51 1
  • It's hard to beat C. This is just slightly faster than the bc version on my machine. real 0m26.856s user 0m25.030s sys 0m0.024s Requirements: libgmp headers, gcc. Show Sample Output


    -5
    gcc -x c -o /tmp/out - -lgmp <<< '#include <stdlib.h> ... SEE SAMPLE OUTPUT FOR FULL COMMAND
    hank · 2009-09-10 02:10:46 3

  • -6
    gcc -Wall -Werror -o prog prog.c || rm -f prog.c
    devoid · 2009-02-05 17:26:51 1
  • Compile *.c files with "gcc -Wall" in actual directory, using as output file the file name without extension.


    -7
    ls *.c | while read F; do gcc -Wall -o `echo $F | cut -d . -f 1 - ` $F; done
    pichinep · 2009-08-28 13:01:56 1

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Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }


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