keikoro

# gcc                       start GNU compiler
# -Wall                     [optional] flag to show warnings (all possible warnings)
# $DESIREDEXECUTABLENAME    [optional] name of resulting executable file; otherwise gcc auto-outputs to a.out 
# $MYFILE.c                 C file that should get compiled

gcc -Wall $DESIREDEXECUTABLENAME $MYFILE.c

keikoro

# ~             find in $HOME
# fdl           file types: f = file, d = directory, l = symbolic link
# $GROUP        current group permission
# -exec         do something with found files
# :$NEWGROUP    new group permission (needs leading colon! -> chown owner:group)
# {}            placeholder for each found file
# \;            escape the semicolon that ends the -exec part of the command

find ~ -type fdl -group $GROUP -print -exec chown :$NEWGROUP {} \;

keikoro

# ~         find in $HOME
# fdl       file types: f = file, d = directory, l = symbolic link
# $GROUP    current group permission

find ~ -type fdl -group $GROUP -print