I couldn’t find much mention of logging utilities for Linux shell scripting (namely Bash), so I wrote my own fairly quickly. I wanted several functions for various levels of logging (info, debug, warning, errors, etc), and a way to adjust what levels can be displayed. I followed the fairly standard convention of using numeric values for these levels and setting a “verbosity” level. If you know of an existing solution for Bash, let me know in the comments. Anyway, here’s the main idea:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | exec 3>&2 # logging stream (file descriptor 3) defaults to STDERR verbosity=2 # default to show warnings silent_lvl=0 err_lvl=1 wrn_lvl=2 inf_lvl=3 dbg_lvl=4 notify() { log $silent_lvl "NOTE: $1"; } # Always prints error() { log $err_lvl "ERROR: $1"; } warn() { log $wrn_lvl "WARNING: $1"; } inf() { log $inf_lvl "INFO: $1"; } # "info" is already a command debug() { log $dbg_lvl "DEBUG: $1"; } log() { if [ $verbosity -ge $1 ]; then # Expand escaped characters, wrap at 70 chars, indent wrapped lines echo -e "$2" | fold -w70 -s | sed '2~1s/^/ /' >&3 fi } |
I added line wrapping and indenting so users don’t have to manually put in line-breaks to get nicer looking outputs, but there is the drawback that it makes the output harder to grep. Perhaps I should add an option to disable the line wrapping.
Here is a longer example with some simple option parsing (apologies for using getopt; I’m currently looking for a better solution).
2 Comments
i am an M Tech student and very much interested in Natural Language Processing, but need some guidance from person like you. Hope you will definitely me.
Thanks
Sure, what do you need guidance with? And what school is M Tech?