File: gawk.info,  Node: Extension Sample Readfile,  Next: Extension Sample Time,  Prev: Extension Sample Read write array,  Up: Extension Samples

17.7.10 Reading an Entire File
------------------------------

The 'readfile' extension adds a single function named 'readfile()', and
an input parser:

'@load "readfile"'
     This is how you load the extension.

'result = readfile("/some/path")'
     The argument is the name of the file to read.  The return value is
     a string containing the entire contents of the requested file.
     Upon error, the function returns the empty string and sets 'ERRNO'.

'BEGIN { PROCINFO["readfile"] = 1 }'
     In addition, the extension adds an input parser that is activated
     if 'PROCINFO["readfile"]' exists.  When activated, each input file
     is returned in its entirety as '$0'.  'RT' is set to the null
     string.

   Here is an example:

     @load "readfile"
     ...
     contents = readfile("/path/to/file");
     if (contents == "" && ERRNO != "") {
         print("problem reading file", ERRNO) > "/dev/stderr"
         ...
     }