head -z for a script (off-topic, but the motivation can be found in this question), but in my CoreOS 835.13.0 I get
head: invalid option -- 'z'.
head --help output:
Usage: head [OPTION]... [FILE]... Print the first 10 lines of each FILE to standard output. With more than one FILE, precede each with a header giving the file name. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -c, --bytes=[-]K print the first K bytes of each file; with the leading '-', print all but the last K bytes of each file -n, --lines=[-]K print the first K lines instead of the first 10; with the leading '-', print all but the last K lines of each file -q, --quiet, --silent never print headers giving file names -v, --verbose always print headers giving file names --help display this help and exit --version output version information and exit K may have a multiplier suffix: b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, and so on for T, P, E, Z, Y. GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Report head translation bugs to <http://translationproject.org/team/> For complete documentation, run: info coreutils 'head invocation'
The funny part is that the last line tells me to run
info coreutils 'head invocation' but I get
info: command not found.