dgsh – Directed Graph Shell

Summary

Report file type, length, and compression performance for data received from the standard input. The data never touches the disk. Demonstrates the use of an output multipipe to source many commands from one followed by an input multipipe to sink to one command the output of many and the use of dgsh-tee that is used both to propagate the same input to many commands and collect output from many commands orderly in a way that is transparent to users. #!/usr/bin/env dgsh tee | {{ printf 'File type:\t' file - printf 'Original size:\t' wc -c printf 'xz:\t\t' xz -c | wc -c printf 'bzip2:\t\t' bzip2 -c | wc -c printf 'gzip:\t\t' gzip -c | wc -c }} | cat Process the Git history, and list the authors and days of the week ordered by the number of their commits. Demonstrates streams and piping through a function. #!/usr/bin/env dgsh forder() { sort | uniq -c | sort -rn } git log --format="%an:%ad" --date=default "$@" | tee | {{ echo "Authors ordered by number of commits" # Order by frequency awk -F: '{print $1}' | forder echo "Days ordered by number of commits" # Order by frequency awk -F: '{print substr($2, 1, 3)}' | forder }} | cat Process a directory containing C source code, and produce a summary of various metrics. Demonstrates nesting, commands without input. #!/usr/bin/env dgsh {{ # C and header code find "$@" \( -name \*.c -or -name \*.h \) -type f -print0 | tee | {{ # Average file name length # Convert to newline separation for counting echo -n 'FNAMELEN: ' tr \\0 \\n | # Remove path sed 's|^.*/||' | # Maintain average awk '{s += length($1); n++} END { if (n>0) print s / n; else print 0; }' xargs -0 /bin/cat | tee | {{ # Remove strings and comments sed 's/#/@/g;s/\\[\\"'\'']/@/g;s/"[^"]*"/""/g;'"s/'[^']*'/''/g" | cpp -P | tee | {{ # Structure definitions echo -n 'NSTRUCT: ' egrep -c 'struct[ ]*{|struct[ ]*[a-zA-Z_][a-zA-Z0-9_]*[ ]*{' #}} (match preceding openings) # Type definitions echo -n 'NTYPEDEF: ' grep -cw typedef # Use of void echo -n 'NVOID: ' grep -cw void # U...