To search for specific lines within a file using tcl, you can use the open
, gets
, and close
commands. Here is an example code snippet that searches for all lines that contain the string "hello" and prints them out:
set input_file "example.txt"
set file_id [open $input_file r]
while {[gets $file_id line] != -1} {
if {[string first "hello" $line] != -1} {
puts $line
}
}
close $file_id
In this code:
set input_file "example.txt"
sets the name of the input file.set file_id [open $input_file r]
opens the file for reading and assigns a file identifier to file_id
.while {[gets $file_id line] != -1}
reads each line of the file until the end of the file is reached (gets
returns -1).if {[string first "hello" $line] != -1}
checks if the line contains the string "hello" using string first
.puts $line
prints out the line if it contains "hello".close $file_id
closes the file once all lines have been read.Please start posting anonymously - your entry will be published after you log in or create a new account. This space is reserved only for answers. If you would like to engage in a discussion, please instead post a comment under the question or an answer that you would like to discuss
Asked: 2022-09-08 11:00:00 +0000
Seen: 16 times
Last updated: Jul 16 '21
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