I have a requirement described in the following.
This just a sample script:
$ cat test.sh
#!/bin/bash
perl -e '
open(IN,"addrss");
open(out,">>addrss");
#newval;
while (<IN>)
{
#col_val=split(/:/);
if ($.==1)
{
for($i=0;$i<=$#col_val;$i++)
{
print("Enter value for $col_val[$i] : ");
chop($newval[$i]=<STDIN>);
}
$str=join(":");
$_="$str"
print OUT;
}
else
{
exit 0;
}
}
close(IN);
close(OUT);
Running this scipt:
$ ./test.sh
Enter value for NAME : abc
Enter value for ADDRESS : asff35
Enter value for STATE : XYZ
Enter value for CITY : EIDHFF
Enter value for CONTACT
: 234656758
$ cat addrss
NAME:ADDRESS:STATE:CITY:CONTACT
abc:asff35:XYZ:EIDHFF:234656758
When I ran it the second time:
$ cat addrss
NAME:ADDRESS:STATE:CITY:CONTACT
abc:asff35:XYZ:EIDHFF:234656758ioret:56fgdh:ghdgh:afdfg:987643221 ## it is appended in the same line...
I want it to be added to the next line.
NOTE:
I want to do this by explitly using the filehandles in Perl and not with redirection operators in shell.
I think you just need to add a newline to your string, before you print it out:
$_="$str\n";
Also, is there a reason why your script executes as bash, and you do a "perl -e" within the script? Why not just make the script file execute as perl?
I think if you add a newline to the end of the string you print, this will work:
$_="$str\n"
print OUT $_ . "\n";
or
instead of print, use printf and add a line feed to the front or back.
Related
MSG_OUT="<B><I>Skipping<N> all libraries and fonts...<N>"
perl -ne '%ES=("B","[1m","I","[3m","N","[m","O","[9m","R","[7m","U","[4m"); while (<>) { s/(<([BINORSU])>)/\e$ES{$2}/g; print; }'
This perl one-liner swaps a token for an escape sequence.
It works as intended but only if the input is surrounded with line feeds.
i.e.
echo "\x0a${MSG_OUT}\x0a" | perl -ne '.... etc.
How do I avoid this issue when reading from stdin?
-n wraps your code in while (<>) { ... }* (cf perldoc perlrun). Thus, your one-liner is equivalent to:
perl -e '
while(<>) {
%ES=("B","[1m","I","[3m","N","[m","O","[9m","R","[7m","U","[4m");
while (<>) { s/(<([BINORSU])>)/\e$ES{$2}/g; print; }
}
'
[Line breaks added for readability. They can be removed if you so desire.]
See the double while (<>) { ... }? That's your issue: the first while (the one added by -n) reads a line, then the second while (the one you wrote) reads a second line, does your s/// (on the second line), and prints this second line updated. Thus, you need a blank line before the actual line you want to process.
To fix the issue, either remove the inner while(<>), or remove the -n flag. For instance:
perl -e '
%ES=("B","[1m","I","[3m","N","[m","O","[9m","R","[7m","U","[4m");
while (<>) { s/(<([BINORSU])>)/\e$ES{$2}/g; print; }
'
Or,
perl -ne '
BEGIN { %ES=("B","[1m","I","[3m","N","[m","O","[9m","R","[7m","U","[4m") };
s/(<([BINORSU])>)/\e$ES{$2}/g; print;
'
Note that instead of using -n and print, you can use -p, which is the same as -n with an extra print** at the end:
perl -pe '
BEGIN { %ES=("B","[1m","I","[3m","N","[m","O","[9m","R","[7m","U","[4m") };
s/(<([BINORSU])>)/\e$ES{$2}/g;
'
* For completness, note that -n adds the label LINE before the while loop (LINE: while(<>) { ... }), although that doesn't matter in your case.
** The print added by -p is actually in a continue block after the while, although, once again, this doesn't matter in your case.
I have a code from perl which I need to convert to .expect script to check if -T is present and then use the next one as a timeout.. basically check the arg count, see if -T is one of them.
Perl code:
# check command line against valid arguments
%opt=();
unless( getopts('T:', \%opt) )
{
print("$progname : Illegal command line arguments\n");
exit(1);
}
$commandTimeout=$opt{T} if $opt{T};
$inputCommand = join(" ", #ARGV); # convert arguments into one (long) string
Expect uses Tcl which is also a general purpose programming language. You can go through the command line arguments by your self.
[user#host] # cat foo.tcl
for {set i 0} {$i < [llength $argv]} {incr i} {
puts "argv\[$i]=[lindex $argv $i]"
}
foreach arg $argv {
puts "$arg"
}
[user#host] # tclsh foo.tcl hello world
argv[0]=hello
argv[1]=world
hello
world
[user#host] #
For more info, see Tcl's doc.
If I run a script with perl -Fsomething, is that something value saved anywhere in the Perl environment where the script can find it? I'd like to write a script that by default reuses the input delimiter (if it's a string and not a regular expression) as the output delimiter.
Looking at the source, I don't think the delimiter is saved anywhere. When you run
perl -F, -an
the lexer actually generates the code
LINE: while (<>) {our #F=split(q\0,\0);
and parses it. At this point, any information about the delimiter is lost.
Your best option is to split by hand:
perl -ne'BEGIN { $F="," } #F=split(/$F/); print join($F, #F)' foo.csv
or to pass the delimiter as an argument to your script:
F=,; perl -F$F -sane'print join($F, #F)' -- -F=$F foo.csv
or to pass the delimiter as an environment variable:
export F=,; perl -F$F -ane'print join($ENV{F}, #F)' foo.csv
As #ThisSuitIsBlackNot says it looks like the delimiter is not saved anywhere.
This is how the perl.c stores the -F parameter
case 'F':
PL_minus_a = TRUE;
PL_minus_F = TRUE;
PL_minus_n = TRUE;
PL_splitstr = ++s;
while (*s && !isSPACE(*s)) ++s;
PL_splitstr = savepvn(PL_splitstr, s - PL_splitstr);
return s;
And then the lexer generates the code
LINE: while (<>) {our #F=split(q\0,\0);
However this is of course compiled, and if you run it with B::Deparse you can see what is stored.
$ perl -MO=Deparse -F/e/ -e ''
LINE: while (defined($_ = <ARGV>)) {
our(#F) = split(/e/, $_, 0);
}
-e syntax OK
Being perl there is always a way, however ugly. (And this is some of the ugliest code I have written in a while):
use B::Deparse;
use Capture::Tiny qw/capture_stdout/;
BEGIN {
my $f_var;
}
unless ($f_var) {
$stdout = capture_stdout {
my $sub = B::Deparse::compile();
&{$sub}; # Have to capture stdout, since I won't bother to setup compile to return the text, instead of printing
};
my (undef, $split_line, undef) = split(/\n/, $stdout, 3);
($f_var) = $split_line =~ /our\(\#F\) = split\((.*)\, \$\_\, 0\);/;
print $f_var,"\n";
}
Output:
$ perl -Fe/\\\(\\[\\\<\\{\"e testy.pl
m#e/\(\[\<\{"e#
You could possible traverse the bytecode instead, since the start probably will be identical every time until you reach the pattern.
Here is the example:
$cat test.tsv
AAAATTTTCCCCGGGG foo
GGGGCCCCTTTTAAAA bar
$perl -wne 'while(<STDIN>){ print $_;}' <test.tsv
GGGGCCCCTTTTAAAA bar
This should work like cat and not like tail -n +2. What is happening here? And what the correct way?
The use of the -n option creates this (taking from man perlrun):
while (<STDIN>) {
while(<STDIN>){ print $_;} #< your code
}
This shows two while(<STDIN>) instances. They both take all available inputs from STDIN, breaking at newlines.
When you run with a test.tsv which is at least two lines long, the first (outer) use of while(<STDIN>) takes the first line, and the second (inner) one takes the second line - so your print statement is first passed the second line.
If you had more than two lines in test.tsv then the inner loop would print out all lines from the second line onwards.
The correct way to make this work is simply to rely on the -n option you pass to perl:
perl -wne 'print $_;' < test.tsv
Because the -n switch implicitly puts your code inside a loop which goes through the file line by line. Remove the 'n' from the list of switches, or (even better) remove your loop from the code, leave only the print command there.
nbokor#nbokor:~/tmp$ perl -wne 'print $_;' <test.csv
AAAATTTTCCCCGGGG foo
GGGGCCCCTTTTAAAA bar
Remove -n command line option. It duplicates while(<STDIN>){ ... }.
$perl -MO=Deparse -wne 'while(<STDIN>){ print $_;}'
BEGIN { $^W = 1; }
LINE: while (defined($_ = <ARGV>)) {
while (defined($_ = <STDIN>)) {
print $_;
}
}
-e syntax OK
I need to search for a specific word in a file starting from specific line and return the line numbers only for the matched lines.
Let's say I want to search a file called myfile for the word my_word and then store the returned line numbers.
By using shell script the command :
sed -n '10,$ { /$my_word /= }' $myfile
works fine but how to write that command on tcl shell?
% exec sed -n '10,$ { /$my_word/= }' $file
extra characters after close-brace.
I want to add that the following command works fine on tcl shell but it starts from the beginning of the file
% exec sed -n "/$my_word/=" $file
447431
447445
448434
448696
448711
448759
450979
451006
451119
451209
451245
452936
454408
I have solved the problem as follows
set lineno 10
if { ! [catch {exec sed -n "/$new_token/=" $file} lineFound] && [string length $lineFound] > 0 } {
set lineNumbers [split $lineFound "\n"]
foreach num $lineNumbers {
if {[expr {$num >= $lineno}] } {
lappend col $num
}
}
}
Still can't find a single line that solve the problem
Any suggestions ??
I don't understand a thing: is the text you are looking for stored inside the variable called my_word or is the literal value my_word?
In your line
% exec sed -n '10,$ { /$my_word/= }' $file
I'd say it's the first case. So you have before it something like
% set my_word wordtosearch
% set file filetosearchin
Your mistake is to use the single quote character ' to enclose the sed expression. That character is an enclosing operator in sh, but has no meaning in Tcl.
You use it in sh to group many words in a single argument that is passed to sed, so you have to do the same, but using Tcl syntax:
% set my_word wordtosearch
% set file filetosearchin
% exec sed -n "10,$ { /$my_word/= }" $file
Here, you use the "..." to group.
You don't escape the $ in $my_word because you want $my_word to be substitued with the string wordtosearch.
I hope this helps.
After a few trial-and-error I came up with:
set output [exec sed -n "10,\$ \{ /$myword/= \}" $myfile]
# Do something with the output
puts $output
The key is to escape characters that are special to TCL, such as the dollar sign, curly braces.
Update
Per Donal Fellows, we do not need to escape the dollar sign:
set output [exec sed -n "10,$ \{ /$myword/= \}" $myfile]
I have tried the new revision and found it works. Thank you, Donal.
Update 2
I finally gained access to a Windows 7 machine, installed Cygwin (which includes sed and tclsh). I tried out the above script and it works just fine. I don't know what your problem is. Interestingly, the same script failed on my Mac OS X system with the following error:
sed: 1: "10,$ { /ipsum/= }": extra characters at the end of = command
while executing
"exec sed -n "10,$ \{ /$myword/= \}" $myfile"
invoked from within
"set output [exec sed -n "10,$ \{ /$myword/= \}" $myfile]"
(file "sed.tcl" line 6)
I guess there is a difference between Linux and BSD systems.
Update 3
I have tried the same script under Linux/Tcl 8.4 and it works. That might mean Tcl 8.4 has nothing to do with it. Here is something else that might help: Tcl comes with a package called fileutil, which is part of the tcllib. The fileutil package contains a useful tool for this case: fileutil::grep. Here is a sample on how to use it in your case:
package require fileutil
proc grep_demo {myword myfile} {
foreach line [fileutil::grep $myword $myfile] {
# Each line is in the format:
# filename:linenumber:text
set lineNumber [lindex [split $line :] 1]
if {$lineNumber >= 10} { puts $lineNumber}
}
}
puts [grep_demo $myword $myfile]
Here is how to do it with awk
awk 'NR>10 && $0~f {print NR}' f="$my_word" "$myfile"
This search for all line larger than line number 10 that contains word in variable $my_word in file name stored in variable myfile