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Merge pull request #4550 from nbehrnd/awk_en

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[awk/en] keep code block within 80 characters/line (maximum)
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Marcel Ribeiro Dantas 2022-11-23 21:16:40 -03:00 committed by GitHub
commit c896683be5
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1 changed files with 18 additions and 13 deletions
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@ -118,12 +118,12 @@ BEGIN {
# Arrays
arr[0] = "foo";
arr[1] = "bar";
# You can also initialize an array with the built-in function split()
n = split("foo:bar:baz", arr, ":");
# You also have associative arrays (actually, they're all associative arrays)
# You also have associative arrays (indeed, they're all associative arrays)
assoc["foo"] = "bar";
assoc["bar"] = "baz";
@ -216,7 +216,8 @@ function string_functions( localvar, arr) {
match(localvar, "t"); # => 4, since the 't' is the fourth character
# Split on a delimiter
n = split("foo-bar-baz", arr, "-"); # a[1] = "foo"; a[2] = "bar"; a[3] = "baz"; n = 3
n = split("foo-bar-baz", arr, "-");
# result: a[1] = "foo"; a[2] = "bar"; a[3] = "baz"; n = 3
# Other useful stuff
sprintf("%s %d %d %d", "Testing", 1, 2, 3); # => "Testing 1 2 3"
@ -238,9 +239,9 @@ function io_functions( localvar) {
# AWK doesn't have file handles, per se. It will automatically open a file
# handle for you when you use something that needs one. The string you used
# for this can be treated as a file handle, for purposes of I/O. This makes
# it feel sort of like shell scripting, but to get the same output, the string
# must match exactly, so use a variable:
# it feel sort of like shell scripting, but to get the same output, the
# string must match exactly, so use a variable:
outfile = "/tmp/foobar.txt";
print "foobar" > outfile;
@ -261,7 +262,7 @@ function io_functions( localvar) {
# Reads a line from a file and stores in localvar
infile = "/tmp/foobar.txt";
getline localvar < infile;
getline localvar < infile;
close(infile);
}
@ -273,10 +274,10 @@ function io_functions( localvar) {
# When you pass arguments to AWK, they are treated as file names to process.
# It will process them all, in order. Think of it like an implicit for loop,
# iterating over the lines in these files. these patterns and actions are like
# switch statements inside the loop.
# switch statements inside the loop.
/^fo+bar$/ {
# This action will execute for every line that matches the regular
# expression, /^fo+bar$/, and will be skipped for any line that fails to
# match it. Let's just print the line:
@ -376,11 +377,15 @@ END {
}
```
Further Reading:
* [Awk tutorial](http://www.grymoire.com/Unix/Awk.html)
* [Awk man page](https://linux.die.net/man/1/awk)
* [The GNU Awk User's Guide](https://www.gnu.org/software/gawk/manual/gawk.html) GNU Awk is found on most Linux systems.
* [The GNU Awk User's Guide](https://www.gnu.org/software/gawk/manual/gawk.html)
GNU Awk is found on most Linux systems.
* [AWK one-liner collection](http://tuxgraphics.org/~guido/scripts/awk-one-liner.html)
* [Awk alpinelinux wiki](https://wiki.alpinelinux.org/wiki/Awk) a technical summary and list of "gotchas" (places where different implementations may behave in different or unexpected ways).
* [Awk alpinelinux wiki](https://wiki.alpinelinux.org/wiki/Awk) a technical
summary and list of "gotchas" (places where different implementations may
behave in different or unexpected ways).
* [basic libraries for awk](https://github.com/dubiousjim/awkenough)