mgetstr

reads a character string from a file

Calling Sequence

str = mgetstr(n, [fd])

Arguments

n non-negative integer:  how many characters should be read.

: :fd an integer: file descriptor as returned by mopen: where

characters should be read. The value -1 stands for the last opened file and is the default.

: :str the character string to be read. :

Description

The mgetstr function attempts to read up to n characters from a file. If end of file is reached before n characters are read, mgetstr returns the properly read values only. As a consequence, when the read cursor is already at the end of the file when mgetstr is called, it returns an empty string no matter what value is provided for n.

Examples

fn = SCI + '/ACKNOWLEDGEMENTS'; // absolute path to some file
details = `fileinfo`_(fn);         // retrieve file details
len = details(1);               // get file length
fd = `mopen`_(fn, 'rt');           // open file as text with read mode
str1 = mgetstr(33, fd)          // read 33 characters from fd
`length`_(str1)                    // 33 characters read
str2 = mgetstr(272, fd)         // read the next 272 characters from fd
`length`_(str2)                    // 272 characters read
`mseek`_(len - 5);                 // jump to the 5th character before end of file
str3 = mgetstr(10, fd)          // try to read 10 characters: returns 5 characters only, no more available
`length`_(str3)                    // yes, there are 5 characters: you just can't see the linefeed :)
str4 = mgetstr(10, fd)          // read 10 characters: returns empty string
`length`_(str4)                    // empty string
`mclose`_(fd);                     // close file descriptor

See Also

• mclose closes an opened file
• meof check if end of file has been reached
• mfprintf converts, formats, and writes data to a file
• fprintfMat writes a matrix in a file
• mfscanf reads input from the stream pointer stream (interface to the C fscanf function)
• fscanfMat reads a matrix from a text file
• mget reads byte or word in a given binary format and converts to a double type
• mopen open a file in Scilab
• mprintf converts, formats, and writes data to the main scilab window
• mput writes byte or word in a given binary format
• mputstr write a character string in a file
• mseek set current position in binary file.
• mtell binary file management
• mdelete deletes file(s)
• “Input/Output functions” section