------------------------------------------------------------------------------
MC logo
Reading Files
[^] Code Examples
------------------------------------------------------------------------------
<<Output Formatting fiin.py Sorted User Lister II>>
#!/usr/bin/python3

# Print the contents of the files listed on the command line.

import sys

for fn in sys.argv[1:]:
    try:
        fin = open(fn, 'r')
    except:
        (type, detail) = sys.exc_info()[:2]
        print("\n*** %s: %s: %s ***" % (fn, type, detail))
        continue
    print("\n*** Contents of", fn, "***")
    
    # Print the file, with line numbers.
    lno = 1
    while 1:
        line = fin.readline()
        if not line: break;
        print('%3d: %-s' % (lno, line[:-1]))
        lno = lno + 1
    fin.close()
print()
This program simply takes a list of files on the command line, and lists the contents of each, with lines numbered.

There are a couple of new things from sys used here.

sys.argv
This gives the list of command line arguments. The first one (position zero) is the name of the script, as in C.
sys.exc_info
This returns a list of information about the current exception. The first item is the name of the exception, the second is the detail information, and the third is the call stack trace-back.
<<Output Formatting Sorted User Lister II>>