Unix Shell Programming Third Edition phần 8 doc

... what shell to start up when you execute a shell escape. In such cases, you want to make sure that each time you start up a new shell, you get the shell you want and not an older Bourne shell. ... you to interactive features of the shell and two shells that have some nice features not found in the POSIX standard shell. Getting the Right Shell Most shells follow a convention...

Ngày tải lên: 13/08/2014, 15:21

... shell, such as bash. Three are covered in the third edition of Unix Shell Programming. It begins with a generalized tutorial of Unix and tools and then moves into detailed coverage of shell programming. Topics ... shell, such as bash. Three are covered in the third edition of Unix Shell Programming. It begins with a generalized tutorial of Unix and tools and then m...

Ngày tải lên: 13/08/2014, 15:21

... "What Is the Shell? ," you should realize that whenever you type something like who | wc -l that you are actually programming in the shell! That's because the shell is interpreting ... into detail on the quoting mechanisms in the shell. Variables Like virtually all programming languages, the shell allows you to store values into variables. A shell variable begin...

Ngày tải lên: 13/08/2014, 15:21

... occurrences of " ;Unix& quot; in the text to " ;UNIX. " This can be easily done in sed as follows: $ sed 's /Unix/ UNIX/' intro Substitute Unix with UNIX The UNIX operating system ... shell also has other responsibilities, as outlined in Figure 3 .8. Figure 3 .8. The shell& apos;s responsibilities. Program Execution The shell is responsible for the execution...

Ngày tải lên: 13/08/2014, 15:21

... who Who's on? root console Jul 8 10:37 barney tty03 Ju1 8 12: 38 fred tty04 Jul 8 13:40 joanne tty07 Jul 8 09:35 tony tty19 Jul 8 08: 30 lulu tty23 Jul 8 09:55 $ on pat pat is not logged on $ ... sample uses of on: $ who root console Jul 8 10:37 barney tty03 Jul 8 12: 38 fred tty04 Jul 8 13:40 joanne tty07 Jul 8 09:35 tony tty19 Jul 8 08: 30 lulu tty23 Jul 8 09:...

Ngày tải lên: 13/08/2014, 15:21

... Send it to the background [1] 9932 $ request id is laser1 -85 (standard input) request id is laser1 -87 (standard input) request id is laser1 -88 (standard input) request id is laser1-92 (standard input) I/O ... special notation is recognized by the shell when writing for commands. If you write for var do command command done (note the absence of the in), the shell automatically seque...

Ngày tải lên: 13/08/2014, 15:21

... subsequently spawned subshells), the standard shell, /usr/bin/sh, is started. From that point on, this new shell processes commands typed in from the terminal. When Ctrl+d is typed to this shell, control ... Goes." cd memos the shell looks at your CDPATH variable to find the memos directory. And if your CDPATH looks like this: $ echo $CDPATH .:/users/steve:/users/steve/docs $ the...

Ngày tải lên: 13/08/2014, 15:21

... 2 and then execute a subshell, which in turn executes other shell programs as subshells. If an interrupt signal is then generated, it will have no effect on the shells or subshells that are executing ... the subshells will be terminated. Suppose that you execute the command The IFS Variable There is a special shell variable called IFS, which stands for Internal Field Separator. The she...

Ngày tải lên: 13/08/2014, 15:21

... command-line option, or after set –o posix is executed. Table 15.4. POSIX Shell, Korn Shell, and Bash Compatibility POSIX Shell Korn Shell Bash ENV file X X POS vi line edit mode X X X emacs line ... (for example, /users/steve/documents) or relative to the current directory (for example, documents, /pat). If CDPATH is non-null and directory is not a full path, the shell search...

Ngày tải lên: 13/08/2014, 15:21

... Bash shell beginning of line, matching 2nd bg command 2nd 3rd 4th 5th 6th books AWK Programming Language, The Learning Pearl Programming Pearl Unix C Shell Field Guide, The Unix in ... Shell Field Guide, The Unix in a Nutshell[colon] System V Edition Unix Programmer's Manual, Volume II Unix Programming Environment, The Bourne shell Bourne, S...

Ngày tải lên: 13/08/2014, 15:21