Listing 1: A make file dependency generator lists the header files required by each object-file target.

A. Listing of the Perl script:

1 #!/usr/bin/perl
2 # @(#) makedepend List make target dependencies
3 # Author: Dale Mensch, July 1993
4 # Modified by: Becca Thomas, January 1994
5 
6 # CONFIGURATION PARAMETERS:
7 
8 # Using GNU make?
9 $have_gmake = 0; # 0 = No, 1 = Yes
10 
11 # Choose the source-file suffix:
12 $source_suffix = '.c'; # Possibilities: .C, .cpp, .cc
13 
14 # Choose the object-file suffix:
15 $object_suffix = '.o'; # Another possibility: .xo
16 
17 # List directories containing header files that don't change:
18 $ignore_include_dirs = '/usr/include'; # Don't need to list these
19 
20 # Location of standard header files:
21 $add_include_dirs = '-I/usr/include'; # If not included automatically
22 
23 # Command that runs preprocessor, includes headers, excludes comments:
24 $cpp_cmd = 'cc -E';
25 
26 # MAIN PROGRAM:
27 
28 # Check correct command line usage:
29 die "Usage: $0 target [target...]\n" unless (@ARGV);# At least one
30 
31 # Open pipe to read make (or gmake) output:
32 if ($have_gmake) {
33 open(MAKE, "gmake -n -W $ARGV[0] |"); # -W outdates target
34 } else {
35 # Rename target because if non-existent it's treated as out-of-date:
36 ($sample_target = $ARGV[0]) =~ s/$source_suffix$/$object_suffix/;
37 if (-e $sample_target) { # If the sample target exists
38 $saved_target = "$sample_target"."~"; # Backup copy name
39 rename($sample_target, $saved_target); # Squirrel away
40 }
41 open(MAKE, "make -n $sample_target |"); # Make treats as dated
42 }
43 
44 # Determine necessary include directives:
45 while (<MAKE>) { # For each make-command output line
46 chop; # Remove trailing newline
47 @cmd_line = split(/[ \t]+/, $_); # Tokenize at whitespace
48 
49 while (@cmd_line) {
50 $make_token = shift (@cmd_line); # For each token
51 if ($make_token =~ /^-I|^-D/) { # Include/define?
52 $directive_token = $make_token; # Yes, save it
53 if (! $is_directive{$directive_token}) { # Not seen
54 $is_directive{$directive_token} .= $directive_token;
55 # Add to catenated string of include directories:
56 $cpp_directives .= " "; # (Catenation saves
57 $cpp_directives .= $directive_token;# original order)
58 }
59 }
60 } # End of while ($make_token = ...
61 } # End of while (<MAKE>) {
62 
63 # Add any necessary include directories:
64 $cpp_directives .= " $add_include_dirs ";
65 
66 # For each source file named on command line
67 while (@ARGV) { # While there are arguments
68 undef %includes; # Reset array before next file
69 $source_file = shift; # Save name for later use
70 if (! -r $source_file) { # Can file be read?
71 print STDERR "Source file \"$source_file\" not readable.\n";
72 next; # Try another source file, if available
73 }
74 # Preprocessor names all include directives:
75 open(CPP, "$cpp_cmd $cpp_directives $source_file |");
76 
77 # Create list of all included files:
78 while (<CPP>) {
79 s#//.*$##; # Delete C++ "//" comment
80 if (/^(#|#line)\s*\d+\s+["<](\S+)[">]\s+.*$/ &&
81 ! m.$ignore_include_dirs. ) { # Grab relevant includes
82 $includes{$2} .= $2 unless $includes{$2}; # Save name
83 } # End of if (/^ ...
84 } # End of while (<CPP>) {
85 
86 # Report target name:
87 $_ = $source_file;
88 s/$source_suffix$/$object_suffix/; # Create target name
89 print "$_ :"; # Dependency or rules line
90 
91 # List the prerequisites for the target:
92 foreach $dependency (sort keys(%includes)) {
93 print " \\\n"; # continuation line
94 print "\t$includes{$dependency}";# Important: tab first
95 }
96 print "\n\n"; # Empty lines between targets
97 }
98 rename($saved_target, $sample_target) if $saved_target;

B. Sample prototype Makefile:

# Make file to build program
#
CFLAGS = -g # for symbolic debugging
#
OBJS = module1.o module2.o
#
program: $(OBJS)
cc -o $@ $(OBJS)
#
# Object file dependencies:
#

C. Completed make file with object-file dependencies included:

# Make file to build program
#
CFLAGS = -g # for symbolic debugging
#
OBJS = module1.o module2.o
#
program: $(OBJS)
cc -o $@ $(OBJS)
#
# Object file dependencies:
#
module1.o : \
./module1.h \
module1.c
module2.o : \
module2.c

Listing 2: The zloop Bourne shell script lets you operate on selected compressed files.

A. Listing of the zloop program:

1 #! /bin/sh
2 # @(#) zloop Loop through compressed files, running command on each
3 # Author: Jerry Peek, April 1990, updated July 1993
4 # Modified by Kees Hendrikse, February 1994
5 
6 Myname=`basename $0` # Name of this program
7 Usage="Usage: $Myname 'command line to run' file.{Z|z|gz|zip}..."
8 
9 # Check command-line arguments:
10 case $# in
11 0|1) echo $Usage 1>&2 ; exit 1 ;;
12 esac
13 
14 # Save command quoting white space:
15 Cmd="$1"; shift # shift away command argument
16 
17 for File # For all remaining arguments (files)
18 do
19 case $File in
20 *.Z) Zcat=zcat ;;
21 *.z) Zcat=pcat ;;
22 *.gz) Zcat=gzcat ;;
23 *.zip) Zcat="unzip -c" ;;
24 *) echo "File type of \"$File\" not recognized." >&2
25 continue ;;
26 esac
27 
28 # Display a header, run the command, report any errors:
29 echo "
30 ==== $Myname: $Zcat $File | $Cmd ====" 1>&2
31 eval $Zcat $File \| $Cmd
32 Status=$?
33 case "$Status" in
34 0) ;;
35 *) echo "Note command that returned $Status exit status:
36 '$Zcat $File | $Cmd'" 1>&2 ;;
37 esac
38 done

B. Using zloop to print some compressed files:

$ ls ch*
ch01.Z ch02.Z ch03.Z ch04.Z ch05.Z
$ zloop 'pr | lp -d ast' ch0[1-3].Z
==== zloop: zcat ch01.Z | pr | lp -d ast ====
request id is ast-1904 (standard input)
==== zloop: zcat ch02.Z | pr | lp -d ast ====
request id is ast-1905 (standard input)
==== zloop: zcat ch03.Z | pr | lp -d ast ====
request id is ast-1906 (standard input)
$ []

C. Discarding the headers from the last example:

$ zloop 'pr | lp -d ast' ch0[1-3].Z 2>/dev/null
request id is ast-1907 (standard input)
request id is ast-1908 (standard input)
request id is ast-1909 (standard input)
$ []

D. Running grep to search for a text in compressed files:

$ zloop 'grep -i "System V"' ch0[12].Z
==== zloop: zcat ch01.Z | grep -i "System V" ====
Note command that returned 1 exit status:
'/usr/bin/zcat ch01.Z | grep -i "System V"'
==== zloop: zcat ch02.Z | grep -i "System V" ====
1 #ifdef TERMIO /* System V or BSD4.3+ */
$ []