OptionScanFileArg

Syntax

char *OptionScanFileArg(FILE *file);

Header

base/option.h

Library

opt

Description

The OptionScanFileArg function extracts a single space separated command line option from an open stream.

The option is read from the stream pointed to by the argument fp. Line beginning with the '#' symbol are ignored and leading spaces are ignored.

The memory used to store the text string should be freed when it is no longer used.

Returns

Returns a pointer to a zero terminated text string containing one command line option. On error, NULL is returned.

Errors

On error, NULL is returned.

Example

Source Code: OptionScanFileArg.c

/* OptionScanFileArg.c
   ===================
   Author: R.J.Barnes
 Copyright (c) 2012 The Johns Hopkins University/Applied Physics Laboratory

This file is part of the Radar Software Toolkit (RST).

RST is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.

Modifications:



#include <stdio.h>
#include <stdlib.h>
#include "option.h"

int main(int argc,char *argv[]) {
  FILE *fp;
  char *text=NULL;

  fp=fopen(argv[argc-1],"r");
  if (fp==NULL) {
    fprintf(stderr,"File not found.'n");
    exit(-1);
  }
  while ((text=OptionScanFileArg(fp)) !=NULL) {
    fprintf(stdout,"%s'n",text);
    free(text);
  }
  fclose(fp); 
  return 0;
}