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1. Shell Programming and Scripting
I need to read a file line by line, then depending on the contents of each line, type in a code that will get written to an array.
The problem I have is when I ask the user to confirm the input code, if it is wrong, how do i Return to ask again?
Any thing I try increments the file to the next... (6 Replies)
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2. Shell Programming and Scripting
I have a txt file with several columns and i want to peform an operation on two columns and output it to a new txt file .
file.txt
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4
4
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3. Shell Programming and Scripting
Hello,
So I sorted my file as I was supposed to:
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> cat file2
in the command line, I got what I was expecting, but in the script itself
...
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4. UNIX for Dummies Questions & Answers
I am trying to ask for full name in a script, Then echo back to the user with the surname only, omitting the first name.
Thanks (2 Replies)
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5. Shell Programming and Scripting
cat myname.txt
John Doe I
John Doe II
John Doe III
-----------------------------------------------------------------------
for i in `cat myname.txt`
do
echo This is my name: $i >> thi.is.my.name.txt
done
-----------------------------------------------------------------------
cat... (1 Reply)
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6. Shell Programming and Scripting
Dear Brothers and Sisters ,
If I use the command date , it will echo out today . How can I get the tomorrow date using the command date ? How to I do the date operation ?
Thanks you very much :):):):):) (1 Reply)
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7. Shell Programming and Scripting
i am new user of unix.i have a question.My script is-
export STR_ALFA=`head -2 "${FILE_PATH}"|tail -1|cut -d"," -f1`
"${TEST_HOME}"/function/chk_alfa.ksh STR_ALFA
now i want to check STR_ALFA:
1)whether is alphabetic
2)whether is numeric
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8. UNIX for Dummies Questions & Answers
Hi
Can anybody tell the difference between Difference between cat , cat > , cat >> and touch command in UNIX?
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9. Shell Programming and Scripting
Hello,
How to undo split operation ? (1 Reply)
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CAT(1) BSD General Commands Manual CAT(1)
NAME
cat -- concatenate and print files
SYNOPSIS
cat [-belnstuv] [file ...]
DESCRIPTION
The cat utility reads files sequentially, writing them to the standard output. The file operands are processed in command-line order. If
file is a single dash ('-') or absent, cat reads from the standard input. If file is a UNIX domain socket, cat connects to it and then reads
it until EOF. This complements the UNIX domain binding capability available in inetd(8).
The options are as follows:
-b Number the non-blank output lines, starting at 1.
-e Display non-printing characters (see the -v option), and display a dollar sign ('$') at the end of each line.
-l Set an exclusive advisory lock on the standard output file descriptor. This lock is set using fcntl(2) with the F_SETLKW command.
If the output file is already locked, cat will block until the lock is acquired.
-n Number the output lines, starting at 1.
-s Squeeze multiple adjacent empty lines, causing the output to be single spaced.
-t Display non-printing characters (see the -v option), and display tab characters as '^I'.
-u Disable output buffering.
-v Display non-printing characters so they are visible. Control characters print as '^X' for control-X; the delete character (octal
0177) prints as '^?'. Non-ASCII characters (with the high bit set) are printed as 'M-' (for meta) followed by the character for the
low 7 bits.
EXIT STATUS
The cat utility exits 0 on success, and >0 if an error occurs.
EXAMPLES
The command:
cat file1
will print the contents of file1 to the standard output.
The command:
cat file1 file2 > file3
will sequentially print the contents of file1 and file2 to the file file3, truncating file3 if it already exists. See the manual page for
your shell (e.g., sh(1)) for more information on redirection.
The command:
cat file1 - file2 - file3
will print the contents of file1, print data it receives from the standard input until it receives an EOF ('^D') character, print the con-
tents of file2, read and output contents of the standard input again, then finally output the contents of file3. Note that if the standard
input referred to a file, the second dash on the command-line would have no effect, since the entire contents of the file would have already
been read and printed by cat when it encountered the first '-' operand.
SEE ALSO
head(1), more(1), pr(1), sh(1), tail(1), vis(1), zcat(1), fcntl(2), setbuf(3)
Rob Pike, "UNIX Style, or cat -v Considered Harmful", USENIX Summer Conference Proceedings, 1983.
STANDARDS
The cat utility is compliant with the IEEE Std 1003.2-1992 (``POSIX.2'') specification.
The flags [-belnstv] are extensions to the specification.
HISTORY
A cat utility appeared in Version 1 AT&T UNIX. Dennis Ritchie designed and wrote the first man page. It appears to have been cat(1).
BUGS
Because of the shell language mechanism used to perform output redirection, the command ``cat file1 file2 > file1'' will cause the original
data in file1 to be destroyed!
The cat utility does not recognize multibyte characters when the -t or -v option is in effect.
BSD
January 29, 2013 BSD