I am using the while-loop to read a file.
The file has lines with null-terminated strings (words, actually.)
What I have by that reading - just a first word up to '\0'!
I need to have whole string up to 'new line' - (LF, 10#10, 16#A)
What I am doing wrong?
#make file 'grb' with... (6 Replies)
Hi All,
I'm trying to figure out which are the trusted-ips and which are not using a script file.. I have a file named 'ip-list.txt' which contains some ip addresses and another file named 'trusted-ip-list.txt' which also contains some ip addresses. I want to read a line from... (4 Replies)
Hi! I have been struggling with a large file that has stray end of line characters.
I am working on a Mac (Lion). I mention this only because I have been mucking around with fixing my problem using sed, and I have learned far more than I wanted to know about Unix and Mac eol characters.
I... (1 Reply)
Hello,
I need a program that read a file line by line and prints out lines 1, 2 & 3 after an empty line... An example of entries in the file would be:
SRVXPAPI001 ERRO JUN24 07:28:34 1775
REASON= 0000, PROCID= #E506 #1065: TPCIPPR, INDEX= 003F
... (8 Replies)
Hi All,
Need an urgent solution to an issue . We have created a ksh file or shell script which generates 1 DAT file. the DAT file contains extract of a select statement .
Now the issue is , when we are executing the ksh file , the output is coimng with page breaks and line breaks .
We have... (4 Replies)
Hi All,
Am trying to write wrapper shell/bash script on a utility tool for which i need to pass 2 files as arugment to execute utility tool.
Wraper script am trying is to do with above metion 2 files.
utility tool accepts :
a. userinfo file : which contains username
b. item file : which... (2 Replies)
Heyas
With my forum search term 'issue with leading dash' i found 2 closed threads which sadly didnt help me.
Also me was to eager to add the script, that i didnt properly test, and just now figured this issue.
So i have this code:
if ]
then while read line
do line="${line/-/'\-'}"... (7 Replies)
Hello,
I'm works on Ubuntu server
My goal : I would like to read file line per line, but i want to started at the end of file.
Currently, I use instructions :
while read line;
do
COMMAND
done < /var/log/apache2/access.log
But, the first line, i don't want this. The file is long... (5 Replies)
Hi All- we have performance issue in unix to read line by line.
I am looking at processing all the records.
description: Our script will read data from a flat file, it will pickup first four character and based on the value it will set up variables accordingly and appended the final output to... (11 Replies)
All- We have a performance issue in reading a file line by line. Please find attached scripts for the same. Currently it is taking some 45 min to parse "512444" lines.
Could you please have a look at it and provide any suggestions to improve the performance.
Thanks,
Balu
... (12 Replies)
Discussion started by: balu1729
12 Replies
LEARN ABOUT OPENDARWIN
cat
CAT(1) BSD General Commands Manual CAT(1)NAME
cat -- concatenate and print files
SYNOPSIS
cat [-benstuv] [file ...]
DESCRIPTION
The cat utility reads files sequentially, writing them to the standard output. The file operands are processed in command-line order. If
file is a single dash ('-') or absent, cat reads from the standard input. If file is a UNIX domain socket, cat connects to it and then reads
it until EOF. This complements the UNIX domain binding capability available in inetd(8).
The options are as follows:
-b Number the non-blank output lines, starting at 1.
-e Display non-printing characters (see the -v option), and display a dollar sign ('$') at the end of each line.
-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 The -u option guarantees that the output is unbuffered.
-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.
DIAGNOSTICS
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 (i.e., 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), 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 [-benstv] 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!
BSD September 15, 2001 BSD