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Post 8031 by Neo on Thursday 4th of October 2001 05:48:46 PM
10-04-2001
Administrator
OK..... if it is 'exec()able' then it:
Does this answer all questions, or just create more ? 
Quote:
The exec family of functions replaces the current process
image with a new process image. The functions described
in this manual page are front-ends for the function
execve(2). (See the manual page for execve for detailed
information about the replacement of the current process.)
The initial argument for these functions is the pathname
of a file which is to be executed.
The const char *arg and subsequent ellipses in the execl,
execlp, and execle functions can be thought of as arg0,
arg1, ..., argn. Together they describe a list of one or
more pointers to null-terminated strings that represent
the argument list available to the executed program. The
first argument, by convention, should point to the file
name associated with the file being executed. The list of
arguments must be terminated by a NULL pointer.
The execv and execvp functions provide an array of point-
ers to null-terminated strings that represent the argument
list available to the new program. The first argument, by
convention, should point to the file name associated with
the file being executed. The array of pointers must be
terminated by a NULL pointer.
The execle function also specifies the environment of the
executed process by following the NULL pointer that termi-
nates the list of arguments in the parameter list or the
pointer to the argv array with an additional parameter.
This additional parameter is an array of pointers to null-
terminated strings and must be terminated by a NULL
pointer. The other functions take the environment for the
new process image from the external variable environ in
the current process.
Some of these functions have special semantics.
The functions execlp and execvp will duplicate the actions
of the shell in searching for an executable file if the
specified file name does not contain a slash (/) charac-
ter. The search path is the path specified in the envi-
ronment by the PATH variable. If this variable isn't
specified, the default path ``:/bin:/usr/bin'' is used.
In addition, certain errors are treated specially.
If permission is denied for a file (the attempted execve
returned EACCES), these functions will continue searching
the rest of the search path. If no other file is found,
however, they will return with the global variable errno
set to EACCES.
image with a new process image. The functions described
in this manual page are front-ends for the function
execve(2). (See the manual page for execve for detailed
information about the replacement of the current process.)
The initial argument for these functions is the pathname
of a file which is to be executed.
The const char *arg and subsequent ellipses in the execl,
execlp, and execle functions can be thought of as arg0,
arg1, ..., argn. Together they describe a list of one or
more pointers to null-terminated strings that represent
the argument list available to the executed program. The
first argument, by convention, should point to the file
name associated with the file being executed. The list of
arguments must be terminated by a NULL pointer.
The execv and execvp functions provide an array of point-
ers to null-terminated strings that represent the argument
list available to the new program. The first argument, by
convention, should point to the file name associated with
the file being executed. The array of pointers must be
terminated by a NULL pointer.
The execle function also specifies the environment of the
executed process by following the NULL pointer that termi-
nates the list of arguments in the parameter list or the
pointer to the argv array with an additional parameter.
This additional parameter is an array of pointers to null-
terminated strings and must be terminated by a NULL
pointer. The other functions take the environment for the
new process image from the external variable environ in
the current process.
Some of these functions have special semantics.
The functions execlp and execvp will duplicate the actions
of the shell in searching for an executable file if the
specified file name does not contain a slash (/) charac-
ter. The search path is the path specified in the envi-
ronment by the PATH variable. If this variable isn't
specified, the default path ``:/bin:/usr/bin'' is used.
In addition, certain errors are treated specially.
If permission is denied for a file (the attempted execve
returned EACCES), these functions will continue searching
the rest of the search path. If no other file is found,
however, they will return with the global variable errno
set to EACCES.
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LEARN ABOUT REDHAT
gzexe
GZEXE(1) General Commands Manual GZEXE(1) NAME
gzexe - compress executable files in place SYNOPSIS
gzexe [ name ... ] DESCRIPTION
The gzexe utility allows you to compress executables in place and have them automatically uncompress and execute when you run them (at a penalty in performance). For example if you execute ``gzexe /bin/cat'' it will create the following two files: -r-xr-xr-x 1 root bin 9644 Feb 11 11:16 /bin/cat -r-xr-xr-x 1 bin bin 24576 Nov 23 13:21 /bin/cat~ /bin/cat~ is the original file and /bin/cat is the self-uncompressing executable file. You can remove /bin/cat~ once you are sure that /bin/cat works properly. This utility is most useful on systems with very small disks. OPTIONS
-d Decompress the given executables instead of compressing them. SEE ALSO
gzip(1), znew(1), zmore(1), zcmp(1), zforce(1) CAVEATS
The compressed executable is a shell script. This may create some security holes. In particular, the compressed executable relies on the PATH environment variable to find gzip and some other utilities (tail, chmod, ln, sleep). BUGS
gzexe attempts to retain the original file attributes on the compressed executable, but you may have to fix them manually in some cases, using chmod or chown. GZEXE(1)