Find replace : Regular expression

[Subra]

Hi,

I have to replace the strings "LINUX", "__linux__", "linux" with
"__linux". Please help me to correct the below script.

My input file is of type below

#ifdef LINUX
DO SOME THING
#end if

#ifdef __linux
DO SOME THING
#endif

#ifdef linux
DO SOME THING
#endif

#ifdef __linux__
DO SOME THING
#endif


My o/p file should be

#ifdef __linux
DO SOME THING
#end if

#ifdef __linux
DO SOME THING
#endif

#ifdef __linux
DO SOME THING
#endif

#ifdef __linux
DO SOME THING
#endif

My script (Which needs correction)
#!/tools/opt/bin/perl
$fileCount = 0;
while($fileCount <= @ARGV-1)
{
open(FileHandle,$ARGV[$fileCount]) || die ("File not present
$ARGV[$fileCount]");
open(OpFile,">OpFile.$ARGV[$fileCount]") || die ("OpFile not
present");
while($line=<FileHandle>)
{
#$line=~s/(^#.*)LINUX(.*)/$1__linux$2/g;
$line=~s/(^#.*)linux(.*)/$1__linux$2/g;
#$line=~s/(^#.*)__linux__(.*)/$1__linux$2/g;

print OpFile $line;
}
close(FileHandle);
$fileCount++;
}

 

[Subra]

I think the below script works
$fileCount = 0;
while($fileCount <= @ARGV-1)
{
open(FileHandle,$ARGV[$fileCount]) || die ("File not present
$ARGV[$fileCount]");
open(OpFile,">OpFile.$ARGV[$fileCount]") || die ("OpFile not
present");
while($line=<FileHandle>)
{
$line=~s/(^#.*)__linux__(.*)/$1__linux$2/g;
$line=~s/(^#.*)LINUX(.*)/$1__linux$2/g;
$line=~s/(^#.*)[\s]+linux(.*)/$1 __linux $2/g;

print OpFile $line;
}
close(FileHandle);
$fileCount++;
}

 

[Gunnar Hjalmarsson]

$line=~s/(^#.*)__linux__(.*)/$1__linux$2/g;
$line=~s/(^#.*)LINUX(.*)/$1__linux$2/g;
$line=~s/(^#.*)[\s]+linux(.*)/$1 __linux $2/g;

That could possibly be written:

$line =~ s/(^#.*?)(?:__)?linux(?:__)?/$1__linux/gi;

 

[Skye Shaw!@#$]

Hi,

I have to replace the strings "LINUX", "__linux__", "linux" with
"__linux". Please help me to correct the below script.

Maybe try this:

[sshaw@localhost ruby]$ perl -i.og -pe'/^#ifdef/ && s/(?:__)?
linux(?:__)?/__linux__/i' file1 file2

file1, file2 will contain the changes. The original files will be save
with a .og extension

I say /^#ifdef/ just in case you are really using `perl -P` on your
source files, <:^|
On another note, has anyone ever used the preprocessor with their perl
programs?

 

[Ala Qumsieh]

$line=~s/(^#.*)__linux__(.*)/$1__linux$2/g;
$line=~s/(^#.*)LINUX(.*)/$1__linux$2/g;
$line=~s/(^#.*)[\s]+linux(.*)/$1 __linux $2/g;

That could possibly be written:

$line =~ s/(^#.*?)(?:__)?linux(?:__)?/$1__linux/gi;

you meant this:

$line =~ s/(^#.*?)(?:__)?linux(?:__)?/${1}__linux/gi;

the OP had it wrong too, and I suspect you just copied/pasted.

--Ala

 

[Gunnar Hjalmarsson]

$line=~s/(^#.*)__linux__(.*)/$1__linux$2/g;
$line=~s/(^#.*)LINUX(.*)/$1__linux$2/g;
$line=~s/(^#.*)[\s]+linux(.*)/$1 __linux $2/g;

That could possibly be written:

$line =~ s/(^#.*?)(?:__)?linux(?:__)?/$1__linux/gi;

you meant this:

$line =~ s/(^#.*?)(?:__)?linux(?:__)?/${1}__linux/gi;

the OP had it wrong too, and I suspect you just copied/pasted.

Well, no, to be honest I didn't think of it, but I had tested the code
before posting.

Now, when I play with various alternatives, it seems as if the braces
are only needed if the string following the dollar-digit variable begins
with a digit.