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请教redhat9.0如何用U盘？
谢！原题
1. Write the UNIX shell.
Even the simplest of real UNIX shells is thousands of lines of C
code. Don't worry, you will be writing a minuscule, super-simplified
shell. Your shell shall accept lines of input from standard input
until EOF. Don't worry about issuing a prompt, command-line editing,
etc. Each line is a command to be executed. The shell should fork to
create a new process in which to run the command, exec the program,
wait for and report the exit status, and report the real, user and
system time consumed by the command. You may assume that each command
is formatted as follows:
command {argument {argument...} }
The above optional arguments are whitespace-delimited, i.e. they are
separated by one or more tabs or spaces. This will simplify parsing. A
line that begins with the # character is a comment and should be
ignored.
Hints: The following system calls will be useful for this project:
fork, exec, and wait4. The C library function gets can be used to read
one line of string. Check their man pages if in doubt. |
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发表于 2004-04-08 07:53
发表于 2004-04-08 07:57
