Commands using gcc (17)

  • 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

  • 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
  • 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 2
  • 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
  • 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


    9
    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
  • 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

  • 0
    gcc -E code.c | sed '/^\#/d' | indent -st -i2 > code-x.c
    enikulenkov · 2012-06-18 22:20:33 0

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


    0
    echo | gcc -dM -E -
    Byung · 2011-05-09 09:59:24 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
  • doesn't need /dev/null Show Sample Output


    4
    gcc -dM -E - <<<''
    bucciarati · 2009-10-28 14:26:56 0

  • 8
    gcc -dM -E - < /dev/null
    ohe · 2009-10-28 14:13:19 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
  • 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
  • /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

  • -6
    gcc -Wall -Werror -o prog prog.c || rm -f prog.c
    devoid · 2009-02-05 17:26:51 1

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Fetch the current human population of Earth

do something else while waiting for an event, such as reboot
until (ssh root@10.1.1.39 2> /dev/null); do date; sleep 15; done In this case will execute "date" then "sleep 15" until we are able to ssh into server, such as after a reboot Could also be like: until ( ping 10.1.1.39 1> /dev/null); do echo "server 10.1.1.39 is down"; sleep 15; done

Sending a file over icmp with hping
you need to start a listening hping on the reciever: hping3 --listen 10.0.2.254 -I eth0 --sign MSGID1 then you can send your file: hping3 10.0.2.254 --icmp --sign MSGID1 -d 50 -c 1 --file a_file

Embed next line on the end of current line using sed
N: On the current line, sed will display it on pattern space, plus a \n (new line); but s/\n//: Will get rid of new line displayed on pattern space, joining the current line's end with the start of the next line Useful in scripts.

Find dead symbolic links

Find the package that installed a command

extract element of xml
poor man's xml parser :)

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" }

Iterate through current directory + all subs for C++ header files and rank by # of comments
This shows you which files are most in need of commenting (one line of output per file)

power off system in X minutes
Replace 60 with the number of minutes until you want the machine to shut down. Alternatively give an absolute time in the format hh:mm (shutdown -h 9:30) Or shutdown right away (shutdown -h now)


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