diff options
author | Akshita Dixit <436_bt19@iiitkalyani.ac.in> | 2022-11-27 14:36:29 +0530 |
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committer | Akshita Dixit <436_bt19@iiitkalyani.ac.in> | 2022-11-27 14:36:29 +0530 |
commit | 66acfb83d14fae742ba8b743adf5d4ea4e65e0c6 (patch) | |
tree | 5bcf01ede6d257d9044fa38b539f2736493938f0 /awk.html.markdown | |
parent | 00b99ceca054f1df1095351ec451ff3787e0efce (diff) | |
parent | 7a505c1d0c3de87d1b3113f815b61790ec4d9ab4 (diff) |
Merge branch 'master' of https://github.com/adambard/learnxinyminutes-docs into docker-docs
Diffstat (limited to 'awk.html.markdown')
-rw-r--r-- | awk.html.markdown | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/awk.html.markdown b/awk.html.markdown index 34013251..dc22a2bd 100644 --- a/awk.html.markdown +++ b/awk.html.markdown @@ -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) |