# gfs_pio_readdelim

## Name

gfs_pio_readdelim -- read one record

## Synopsis

    #include <gfarm/gfarm.h>

```char *gfs_pio_readdelim``(GFS_File `f`, char **`bufp`, size_t *`sizep`, size_t *`lenp`, char *`delimiter`, size_t `delimlen`);`

## DESCRIPTION

`gfs_pio_readdelim()` works like `gfs_pio_readline()`, except a delimiter of input records is not always newline, and can be specified. This function reads one record from the file specified by the parameter `gf`, by using the parameter `delimiter` as the delimiter of the input records. You can include '\0' character in the `delimiter`, So, you have to specify the length of the `delimiter` by the parameter `delimlen`. If parameter `delimiter` is NULL, this function reads entire file as one record. Otherwise, and if the parameter `delimlen` is 0, this function treats two or more consecutive empty lines (/\n\n+/ in a regular expression) as the input delimiter. This feature is derived from INPUT_RECORD_SEPARATOR in perl language.

Parameter `bufp` specifies an address of a pointer variable initialzed by NULL at first. `gfs_pio_readdelim()` allocates a buffer for I/O dynamically, and stores the address of the buffer to this variable pointed by `bufp`. Parameter `sizep` specifies an address of a size_t variable initialized by 0. This size_t variable is used to record the size of the buffer. Or, you can specify a buffer allocated by malloc(3) in the variable pointed by the parameter `bufp`. In this case, you have to specify the size of the allocated buffer by the parameter `sizep`. If the length of the record exceeds the size of the buffer, the buffer will be automatically realloc(3)ed, and the variable pointed by `bufp` and `sizep` will be updated respectively. Note that you are responsible to free(3) this buffer.

This function returns the length of the record to a variable pointed by the parameter `lenp`. This length includes the length of the record delimiter.

This function doesn't remove the delimiter at the end of records. Also, despite that you can use the value returned by the variable pointed by `lenp`, this function always appends \0' character at the end of records.

If the file reaches its end, the length of the result record becomes 0.

gfs_pio_readdelim(f, bufp, sizep, lenp, "\n", 1) is equivalent to `gfs_pio_readline()` function.

## RETURN VALUES

`NULL`

  The function terminated successfully.

`GFARM_ERR_NO_MEMORY`

  Insufficient memory was available.

  Note that you need to free(3) the buffer pointed by the parameter `bufp`

Others

  An error except the above occurred. The reason is shown by its pointed strings.

## EXAMPLES

Example 1. Example of `gfs_pio_readdelim` function

    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <gfarm/gfarm.h>

    int
    main(int argc, char **argv)
    {
    	char *e;
    	GFS_File gf;
    	size_t bufsize = 0, delimlen = 1, len;
    	char *buffer = NULL, *delim = "\n";

    	e = gfarm_initialize(&argc, &argv);
    	if (e != NULL) {
    		fprintf(stderr, "gfarm_initialize: %s\n", e);
    		return (EXIT_FAILURE);
    	}
    	while ((c = getopt(argc, argv, "d:D")) != -1) {
    		switch (c) {
    		case 'd':
    			delim = optarg;
    			delimlen = strlen(optarg);
    			break;
    		case 'D':
    			delim = NULL;
    			delimlen = 0;
    			break;
    		case '?':
    		default:
    			fprintf(stderr, "invalid option: %c\n", c);
    			return (EXIT_FAILURE);
    		}
    	}
    	if (optind >= argc) {
    		fprintf(stderr, "missing gfarm filename\n");
    		return (EXIT_FAILURE);
    	}
    	e = gfs_pio_open(argv[optind], GFARM_FILE_RDONLY, &gf);
    	if (e != NULL) {
    		fprintf(stderr, "%s: %s\n", argv[optind], e);
    		return (EXIT_FAILURE);
    	}
    	e = gfs_pio_set_view_global(gf, 0);
    	if (e != NULL) {
    		fprintf(stderr, "%s: gfs_pio_set_view_global: %s\n",
    		    argv[optind], e);
    		return (EXIT_FAILURE);
    	}

    	while ((e = gfs_pio_readdelim(gf, &buffer, &bufsize, &len,
    	    delim, delimlen)) == NULL && len > 0) {
    		printf("<%6d/%6d >%s", len, bufsize, buffer);
    	}
    	if (buffer != NULL)
    		free(buffer);
    	if (e != NULL) {
    		fprintf(stderr, "ERROR: %s\n", e);
    		return (EXIT_FAILURE);
    	}
    	e = gfs_pio_close(gf);
    	if (e != NULL) {
    		fprintf(stderr, "gfs_pio_close: %s\n", e);
    		return (EXIT_FAILURE);
    	}
    	e = gfarm_terminate();
    	if (e != NULL) {
    		fprintf(stderr, "gfarm_initialize: %s\n", e);
    		return (EXIT_FAILURE);
    	}
    	return (EXIT_SUCCESS);
    }

## SEE ALSO

gfs_pio_open(3), gfs_pio_getline(3), gfs_pio_gets(3), gfs_pio_readline(3)