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shc(1)                 DragonFly General Commands Manual                shc(1)

NAME
       shc - Generic shell script compiler

SYNOPSIS
       shc [ -e date ] [ -m addr ] [ -i iopt ] [ -x cmnd ]
       [ -l lopt ] [ -ACDhTv ] -f script

DESCRIPTION
       shc creates a stripped binary executable version of the script
       specified with -f on the command line.

       The binary version will get a .x extension appended and will usually be
       a bit larger in size than the original ascii code.  Generated C source
       code is saved in a file with the extension .x.c

       If you supply an expiration date with the -e option the compiled binary
       will refuse to run after the date specified.  The message "Please
       contact your provider" will be displayed instead.  This message can be
       changed with the -m option.

       You can compile any kind of shell script, but you need to supply valid
       -i, -x and -l options.

       The compiled binary will still be dependent on the shell specified in
       the first line of the shell code (i.e. #!/bin/sh), thus shc does not
       create completely independent binaries.

       shc itself is not a compiler such as cc, it rather encodes and encrypts
       a shell script and generates C source code with the added expiration
       capability. It then uses the system compiler to compile a stripped
       binary which behaves exactly like the original script. Upon execution,
       the compiled binary will decrypt and execute the code with the shell -c
       option.  Unfortunatelly, it will not give you any speed improvement as
       a real C program would.

       shc's main purpose is to protect your shell scripts from modification
       or inspection. You can use it if you wish to distribute your scripts
       but don't want them to be easily readable by other people.

OPTIONS
       The command line options are:

       -e date
              Expiration date in dd/mm/yyyy format [none]

       -m message
              message to display upon expiration ["Please contact your
              provider"]

       -f script_name
              File name of the script to compile

       -i inline_option
              Inline option for the shell interpreter i.e: -e

       -x comand
              eXec command, as a printf format i.e: exec(\\'%s\\',@ARGV);

       -l last_option
              Last shell option i.e: --

       -r     Relax security. Make a redistributable binary which executes on
              different systems running the same operating system.

       -v     Verbose compilation

       -D     Switch on debug exec calls

       -T     Allow binary to be traceable (using strace, ptrace, truss, etc.)

       -C     Display license and exit

       -A     Display abstract and exit

       -h     Display help and exit

ENVIRONMENT VARIABLES
       CC     C compiler command [cc]

       CFLAGS C compiler flags [none]

EXAMPLES
       Compile a script which can be run on other systems with the trace
       option enabled:

         example% shc -v -r -T -f myscript

BUGS
       The maximum size of the script that could be executed once compiled is
       limited by the operating system configuration parameter _SC_ARG_MAX
       (see sysconf(2))

AUTHOR
       Francisco Rosales <frosal@fi.upm.es>

REPORT BUGS TO
       the author.

4th Berkeley Distribution        June 18, 2003                          shc(1)