SCO(1) BSD Reference Manual SCO(1)NAME
sco - access to SCO / iBCS2 emulation
SYNOPSIS
sco program arguments ...
DESCRIPTION
The sco program creates an incomplete, imitation SCO environment for exe-
cution. Its most typical use is to run a shell:
$ sco sh
$
The SCO environment is created by loading the given program with the SCO
emulator (see ibcs2(5)). The emulator maps BSD/OS pathnames to SCO path-
names, using the /sco/filemap file. This feature allows (for example)
the BSD/OS /var/tmp directory to appear as /usr/tmp without adding sym-
links or other clutter to the filesystem, and it is used to translate a
number of standard SCO pathnames. The emulator is loaded automatically
when you execute an iBCS2-format SCO program, so it isn't necessary to
run such programs directly with sco.
For users' convenience, the sco program also alters a couple of environ-
ment variables in a way that makes them more useful in the SCO environ-
ment. The PATH variable is altered to put /etc in root's path, and to
force sh(1) to check for built-in commands only after first checking for
commands of the same name in the user's path. The latter change allows
sh(1) to use a SCO-compatible version of echo(1) instead of the built-in
version, for example. The sco program also alters the user's DISPLAY
variable, if set, so that it uses TCP to reach a local X server rather
than STREAMS; STREAMS connections are not currently supported for pro-
grams that don't use the shared NSL library.
FILES
/sco/emulator the emulator image
/sco/filemap the filename translation table
SEE ALSOibcs2(5)BUGS
Some shells work better with sco than other shells; sco is currently op-
timized for sh(1).
Job control characters don't work in the SCO environment. However, it is
still possible to stop a SCO job with kill(1).
It's possible to fall out of the SCO namespace using relative pathnames.
You must resort to a kluge to name a BSD file that is concealed by a
filename mapping. The current convention is to use two slashes at the
start of the pathname, for example //bin/df. This defeats the filename
mapping and names the BSD df instead of a script that imitates the SCO
df.
For more bugs with emulation, see ibcs2(5).
BSDI BSD/OS November 1, 1996 1