Python 2.7+ script for printing a FITS header. Accepts multiple files and, optionally, keywords. This is a wrapper around pyfits.getheader to make it accessible from the command line.

imhead.py

#!/usr/bin/env python
"""
Print a FITS header or keyword. Type imhead -h for help.

Requires pyfits and Python 2.7+.

Author
------
@jiffyclub
git.io/jiffyclub

Examples
--------

Print a header:

imhead jb1f98q1q_raw.fits

Print an extension header:

imhead -e 1 jb1f98q1q_raw.fits

Print only specified keywords:

imhead jb1f98q1q_raw.fits -k expstart -k expend

"""

import argparse

import pyfits


def print_header(fits, ext=0, keys=None):
    head = pyfits.getheader(fits, ext=ext).ascard

    if not keys:
        print head
    else:
        for key in keys:
            print head[key]


def parse_args():
    parser = argparse.ArgumentParser(description=
                                     'Print a FITS header or keyword.')

    parser.add_argument('fits_files', nargs='+', type=str,
                        help='Name of fits files.')

    parser.add_argument('-e', '--ext', type=int, default=0,
                        help='Extension number. Defaults to 0.')

    parser.add_argument('-k', '--key', type=str, action='append',
                        help='Keyword to print. May occur multiple times.')

    return parser.parse_args()


def main():
    args = parse_args()
  
    for fits_file in args.fits_files:
        print_header(fits_file, args.ext, args.key)


if __name__ == '__main__':
    raise SystemExit(main())

A Python 2.3+ version of this that uses optparse is also available: https://gist.github.com/1401692.