09-03-2009
Quote:
Originally Posted by
niceguyeddie
Hi
./myprogram <&4 &
Then later:
echo "inputstring" >&4
then later again
cat somefile >&4
This results is bash telling me "Bad file descriptor" when I start ./myprogram
The whole point of this is to exercise a library that I've written. Its wrapped in a C frontend that takes input from stdin (like a psuedo command line program). It's got to stay alive though so the data in my library under test can stay persistent.
Any idea if this is possible?
Um, you can't use a file descriptor that does not exist (hopefully you have prepared your C code better :-)
As mentioned earlier, you should create a FIFO (a special file). Have a look at mknod's manual page (parameter
p is what you are looking for).
pen
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LEARN ABOUT FREEBSD
atf-sh
ATF-SH(1) BSD General Commands Manual ATF-SH(1)
NAME
atf-sh [-s shell] -- interpreter for shell-based test programs
SYNOPSIS
atf-sh script
DESCRIPTION
atf-sh is an interpreter that runs the test program given in script after loading the atf-sh(3) library.
atf-sh is not a real interpreter though: it is just a wrapper around the system-wide shell defined by ATF_SHELL. atf-sh executes the inter-
preter, loads the atf-sh(3) library and then runs the script. You must consider atf-sh to be a POSIX shell by default and thus should not
use any non-standard extensions.
The following options are available:
-s shell Specifies the shell to use instead of the value provided by ATF_SHELL.
ENVIRONMENT
ATF_LIBEXECDIR Overrides the builtin directory where atf-sh is located. Should not be overridden other than for testing purposes.
ATF_PKGDATADIR Overrides the builtin directory where libatf-sh.subr is located. Should not be overridden other than for testing purposes.
ATF_SHELL Path to the system shell to be used in the generated scripts. Scripts must not rely on this variable being set to select a
specific interpreter.
EXAMPLES
Scripts using atf-sh(3) should start with:
#! /usr/bin/env atf-sh
Alternatively, if you want to explicitly choose a shell interpreter, you cannot rely on env(1) to find atf-sh. Instead, you have to hardcode
the path to atf-sh in the script and then use the -s option afterwards as a single parameter:
#! /path/to/bin/atf-sh -s/bin/bash
ENVIRONMENT
ATF_SHELL Path to the system shell to be used in the generated scripts.
SEE ALSO
atf-sh(3)
BSD
September 27, 2014 BSD