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 11

  • 8
    gcc -dM -E - < /dev/null
    ohe · 2009-10-28 14:13:19 11
  • 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 10
  • /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 88
  • doesn't need /dev/null Show Sample Output


    4
    gcc -dM -E - <<<''
    bucciarati · 2009-10-28 14:26:56 3
  • 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 7

  • 2
    gcc -dM -E - < /dev/null
    lucasrangit · 2012-04-27 17:37:50 8
  • another one


    0
    echo | gcc -dM -E -
    Byung · 2011-05-09 09:59:24 4

  • 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 4

  • 0
    gcc -E code.c | sed '/^\#/d' | indent -st -i2 > code-x.c
    enikulenkov · 2012-06-18 22:20:33 5
  • 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 7
  • 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 7

  • 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 8
  • 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 5
  • 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 8

  • -6
    gcc -Wall -Werror -o prog prog.c || rm -f prog.c
    devoid · 2009-02-05 17:26:51 20
  • 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 9

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List the size (in human readable form) of all sub folders from the current location

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if you need a quick way of printing out all the packages that contain classes this command will print the directory structure and replace '/' with '.' It will also ignore CVS directories (we use CVS here)

Rsync between two servers
copying files from one server to another using rysnc. Root access need to be allowed on the destination.

Go up multiple levels of directories quickly and easily.
Change to your taste. Much quicker than having to add 'cd' every time. Add it to your .bashrc or .bash_profile.

View all file operator expressions for any file, test, stat
Applies each file operator using the built-in test. $ testt /home/askapache/.sq /home/askapache/.sq -a True - file exists. -d True - file is a directory. -e True - file exists. -r True - file is readable by you. -s True - file exists and is not empty. -w True - the file is writable by you. -x True - the file is executable by you. -O True - the file is effectively owned by you. -G True - the file is effectively owned by your group. -N True - the file has been modified since it was last read. Full Function: testt () { local dp; until [ -z "${1:-}" ]; do dp="$1"; [[ ! -a "$1" ]] && dp="$PWD/$dp"; command ls -w $((${COLUMNS:-80}-20)) -lA --color=tty -d "$dp"; [[ -d "$dp" ]] && find "$dp" -mount -depth -wholename "$dp" -printf '%.5m %10M %#15s %#9u %-9g %#5U %-5G %Am/%Ad/%AY %Cm/%Cd/%CY %Tm/%Td/%TY [%Y] %p\n' -a -quit 2> /dev/null; for f in a b c d e f g h L k p r s S t u w x O G N; do test -$f "$dp" && help test | sed "/-$f F/!d" | sed -e 's#^[\t ]*-\([a-zA-Z]\{1\}\) F[A-Z]*[\t ]* True if#-\1 "'$dp'" #g'; done; shift; done }

resize all JPG images in folder and create new images (w/o overwriting)
Convert all jpegs in the current directory into ~1024*768 pixels and ~ 150 KBytes jpegs

Convert JSON to YAML
You need to install the Catmandu Perl module via `cpanm Catmandu`

SED - Substitute string in next line
source: http://sed.sourceforge.net/sed1line.txt

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Dump snapshot of UFS2 filesystem, then gzip it
Opens a snapshot of a live UFS2 filesystem, runs dump to generate a full filesystem backup which is run through gzip. The filesystem must support snapshots and have a .snap directory in the filesystem root. To restore the backup, one can do $ zcat /path/to/adXsYz.dump.gz | restore -rf -


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