Copyright Sams Teach Yourself Shell Programming in 24 Hours

77 if [ $? -ne 0 ] ; then
78 printERROR "Unable to successfully move $1 to $2"
79 fi
80
81 # if a rename of the copy is requested
82
83 if [ -n "$NEWNAME" ] ; then
84
85 # try and change to the destination directory
86
87 cd "$DESTDIR" > /dev/null 2>&1
88 if [ $? -ne 0 ] ; then
89 printERROR "Could not cd to $DESTDIR"
90 fi
91
92 # try and rename the copy
93
94 /bin/mv "$SRCDIR_CHILD" "$NEWNAME" > /dev/null 2>&1
95 if [ $? -ne 0 ] ; then
96 printERROR "Could not rename $1 to $2"
97 fi
98
99 # return to the original directory
100
101 cd "$SRCDIR_PARENT" > /dev/null 2>&1
102 if [ $? -ne 0 ] ; then
103 printERROR "Could not cd to $SRCDIR_PARENT"
104 fi
105 fi
106
107 # try and remove the original
108
109 if [ -d "$SRCDIR_CHILD" ] ; then
110 /bin/rm -r "$SRCDIR_CHILD" > /dev/null 2>&1
111 if [ $? -ne 0 ] ; then
112 printERROR "Could not remove $1"
113 fi
114 fi
115
116 exit 0
A Walkthrough of mvdir.sh
I'll walk through the script and highlight some of the important points.
The first thing this script does is set the PATH variable (line 7). You do this to ensure that all the commands
you use come from one of the two directories that you specified. When you write a script that can be run by
many users, you have to take into account that some users might have modified their PATH such that the
commands you are using are inaccessible or replaced by other versions. By setting the PATH variable
explicitly, you avoid this problem.
Next the script defines a few utility functions (lines 11 and 15) used to print error usage messages. You can