12 <concept id="GUID-310A8A9C-98E7-59EE-9376-8E572580190F" xml:lang="en"><title>File

    12 <concept id="GUID-310A8A9C-98E7-59EE-9376-8E572580190F" xml:lang="en"><title>File services in Symbian platform</title><shortdesc>This topic describes the common concepts of file systems

    13 services in Symbian platform</title><shortdesc>This topic describes the common concepts of file systems and files

    13 and files used by Symbian platform.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    14 used by Symbian platform.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    14 <p>Like other software systems, Symbian platform can store data so

    15 <p>Like other software systems, Symbian platform can store data so that it

    15 that it is kept when a handset is powered down. </p>

    16 is kept when a handset is powered down. </p>

    16 <p>On PCs, a file is kept on magnetic disk or optical media such as

    17 <p>On PCs, a file is kept on magnetic disk or optical media such as CD or

    17 CD or DVD. On older generations of personal organisers, a file was

    18 DVD. On older generations of personal organisers, a file was often kept in

    18 often kept in RAM, needing a permanent power supply, and a backup

    19 RAM, needing a permanent power supply, and a backup battery to guarantee this.

    19 battery to guarantee this. On the most recent telephone handsets,

    20 On the most recent telephone handsets, files are normally stored in flash

    20 files are normally stored in flash memory, either NOR flash or NAND

    21 memory, either NOR flash or NAND flash, and also on removable devices such

    21 flash, and also on removable devices such as MultiMediaCard (MMC),

    22 as MultiMediaCard (MMC), Secure Digital card (SD card), Memory Stick or Compact

    22 Secure Digital card (SD card), Memory Stick or Compact flash (CF). </p>

    23 flash (CF). </p>

    23 <p>There are more sophisticated services for persisting data such

    24 <p>There are more sophisticated services for persisting data such as streams,

    24 as streams, stores, central repository etc. that applications can

    25 stores, central repository etc. that applications can use, but they all rely,

    25 use, but they all rely, either directly or indirectly, on the commonly

    26 either directly or indirectly, on the commonly understood idea of the file. </p>

    26 understood idea of the file. </p>

    27 <p>The ROM on a typical handset is located in non-volatile flash memory, allowing

    27 <p>The ROM on a typical handset is located in non-volatile flash memory,

    28 it to be upgraded by the handset manufacturer after initial production. The

    28 allowing it to be upgraded by the handset manufacturer after initial

    29 location for user data is almost always flash memory (NAND or NOR), on the

    29 production. The location for user data is almost always flash memory

    30 grounds of cost, although rotating media devices capable of holding large

    30 (NAND or NOR), on the grounds of cost, although rotating media devices

    31 amounts of data are likely in future handsets. </p>

    31 capable of holding large amounts of data are likely in future handsets. </p>

    38 <section id="GUID-DD8C4BFB-9816-5EA5-A9F2-5146C64BBC9C"><title>Basic concepts</title> <p>Symbian

    38 <section id="GUID-DD8C4BFB-9816-5EA5-A9F2-5146C64BBC9C"><title>Basic

    39 platform uses a number of file concepts that are common to most operating

    39 concepts</title> <p>Symbian platform uses a number of file concepts

    40 systems, for example, drives and directories. </p> <p><b>Drives</b> </p> <p>Symbian

    40 that are common to most operating systems, for example, drives and

    41 platform uses the concept of the <i>drive</i>. This idea is similar to that

    41 directories. </p> <p><b>Drives</b> </p> <p>Symbian platform uses the concept of the <i>drive</i>. This idea is similar to that in other operating systems,

    42 in other operating systems, i.e. it corresponds to a logical device. A media

    42 i.e. it corresponds to a logical device. A media device such as a

    43 device such as a MultiMediaCard can be logically split into partitions, and

    43 MultiMediaCard can be logically split into partitions, and each partition

    44 each partition is treated as a separate drive. Symbian platform adopts a DOS-like

    44 is treated as a separate drive. Symbian platform adopts a DOS-like

    45 convention where each drive is identified by a single letter. This means that

    45 convention where each drive is identified by a single letter. This

    46 there can be up to 26 drives on a handset, identified by the letters <filepath>A:</filepath> through

    46 means that there can be up to 26 drives on a handset, identified by

    47 to <filepath>Z:</filepath>. In practice, there are far fewer than this, and

    47 the letters <filepath>A:</filepath> through to <filepath>Z:</filepath>. In practice, there are far fewer than this, and the number depends

    48 the number depends on the individual manufacturer's handset </p> <p>Internally,

    48 on the individual manufacturer's handset </p> <p>Internally, Symbian

    49 Symbian platform uses the idea of a drive number instead of a letter, and

    49 platform uses the idea of a drive number instead of a letter, and

    50 some legacy API items take a drive number as input, or return a drive number

    50 some legacy API items take a drive number as input, or return a drive

    51 as output. However, there are functions that can translate drive numbers to

    51 number as output. However, there are functions that can translate

    52 and from drive letters: <xref href="GUID-E263C747-946F-35AA-9F1D-41833BD350FC.dita#GUID-E263C747-946F-35AA-9F1D-41833BD350FC/GUID-A0F50C51-A4F0-33C1-BBD4-757DEC4B7F2E"><apiname>RFs::DriveToChar()</apiname></xref> and <xref href="GUID-E263C747-946F-35AA-9F1D-41833BD350FC.dita#GUID-E263C747-946F-35AA-9F1D-41833BD350FC/GUID-D545B868-0549-37A9-AACE-288E7C9CE8C3"><apiname>RFs::CharToDrive()</apiname></xref>. </p> <p>The

    52 drive numbers to and from drive letters: <xref href="GUID-E263C747-946F-35AA-9F1D-41833BD350FC.dita#GUID-E263C747-946F-35AA-9F1D-41833BD350FC/GUID-A0F50C51-A4F0-33C1-BBD4-757DEC4B7F2E"><apiname>RFs::DriveToChar()</apiname></xref> and <xref href="GUID-E263C747-946F-35AA-9F1D-41833BD350FC.dita#GUID-E263C747-946F-35AA-9F1D-41833BD350FC/GUID-D545B868-0549-37A9-AACE-288E7C9CE8C3"><apiname>RFs::CharToDrive()</apiname></xref>. </p> <p>The main ROM

    53 main ROM on a handset is always identified as the <filepath>Z:</filepath> drive.

    53 on a handset is always identified as the <filepath>Z:</filepath> drive.

    54 Other drives may be in use: sixteen of the drives <filepath>C:</filepath> to <filepath>R:</filepath> are

    54 Other drives may be in use: sixteen of the drives <filepath>C:</filepath> to <filepath>R:</filepath> are usually reserved as local drives,

    55 usually reserved as local drives, i.e. for media devices located within the

    55 i.e. for media devices located within the handset. A common convention

    56 handset. A common convention is to adopt <filepath>C:</filepath> as the main

    56 is to adopt <filepath>C:</filepath> as the main user data drive. and

    57 user data drive. and to designate <filepath>D:</filepath> or <filepath>E:</filepath> as

    57 to designate <filepath>D:</filepath> or <filepath>E:</filepath> as

    58 drives for removable media. <i>Be aware</i>, however, that this is a convention

    58 drives for removable media. <i>Be aware</i>, however, that this is

    59 that some handset manufacturers may not follow, so you are always advised

    59 a convention that some handset manufacturers may not follow, so you

    60 to check the full SDK that applies to a specific handset for guidance. Indeed,

    60 are always advised to check the full SDK that applies to a specific

    61 as a matter of principle, you should always use the <xref href="GUID-629AB2C9-BEDD-5166-8B09-F8DFF7527C03.dita">system

    61 handset for guidance. Indeed, as a matter of principle, you should

    62 drive</xref> for user data. </p> <p><b>Volume</b> </p> <p>The concept of the volume applies to removable media. As users insert

    62 always use the <xref href="GUID-629AB2C9-BEDD-5166-8B09-F8DFF7527C03.dita">system drive</xref> for user data. </p> <p><b>Volume</b> </p> <p>The concept of the volume applies to removable

    63 and remove individual devices, so different volumes are said to be mounted

    63 media. As users insert and remove individual devices, so different

    64 and demounted. For media types that can be split into partitions, each partition

    64 volumes are said to be mounted and demounted. For media types that

    65 corresponds to a separate volume. </p> <p><b>File

    65 can be split into partitions, each partition corresponds to a separate

    66 names and directory structures</b> </p> <p>Files have names, and Symbian platform

    66 volume. </p> <p><b>File names and directory structures</b> </p> <p>Files have names,

    67 uses a hierarchical directory structure in which to organize them; this is

    67 and Symbian platform uses a hierarchical directory structure in which

    68 similar to schemes adopted by other operating systems. For example: </p> <codeblock id="GUID-C4330879-E93B-5939-A810-8D4A1E5B14DB" xml:space="preserve">C:\AAA\BBB\CCC\DDD.EXT</codeblock> <p>There

    68 to organize them; this is similar to schemes adopted by other operating

    69 are four main parts to the structure: </p> <ul>

    69 systems. For example: </p> <codeblock id="GUID-C4330879-E93B-5939-A810-8D4A1E5B14DB" xml:space="preserve">C:\AAA\BBB\CCC\DDD.EXT</codeblock> <p>There are four main parts to the structure: </p> <ul>

    70 <li id="GUID-39D18587-8793-511F-B3CC-8CFA6D129F80"><p>the <i>drive</i>; this

    70 <li id="GUID-39D18587-8793-511F-B3CC-8CFA6D129F80"><p>the <i>drive</i>; this is always at the top of the hierarchy, and is represented

    71 is always at the top of the hierarchy, and is represented by a drive letter

    71 by a drive letter and a colon. </p> </li>

    72 and a colon. </p> </li>

    72 <li id="GUID-8F5F5EB0-721F-5C5B-90B6-08E2CB92BA98"><p>the <i>path</i>; this is a list of names, each name representing a level in the

    73 <li id="GUID-8F5F5EB0-721F-5C5B-90B6-08E2CB92BA98"><p>the <i>path</i>; this

    73 hierarchy. Each directory name is separated by a back slash character,

    74 is a list of names, each name representing a level in the hierarchy. Each

    74 and the last directory name is always terminated by a back slash character. </p> </li>

    75 directory name is separated by a back slash character, and the last directory

    75 <li id="GUID-BD848A50-9BEA-5E08-ACDB-92EDB9C5CA86"><p>the <i>filename</i>; this is everything after the final backslash, and before the dot

    76 name is always terminated by a back slash character. </p> </li>

    76 if there is a file extension. Symbian platform supports long file

    77 <li id="GUID-BD848A50-9BEA-5E08-ACDB-92EDB9C5CA86"><p>the <i>filename</i>;

    77 filenames. </p> </li>

    78 this is everything after the final backslash, and before the dot if there

    78 <li id="GUID-07E1D5CB-9D9B-5141-AD7B-76F839AA2FC0"><p>the <i>extension</i>, everything after the final dot. There is no restriction on the

    79 is a file extension. Symbian platform supports long file filenames. </p> </li>

    79 length of the extension; limits on length apply to the whole structure,

    80 <li id="GUID-07E1D5CB-9D9B-5141-AD7B-76F839AA2FC0"><p>the <i>extension</i>,

    80 not to any single part of it. </p> </li>

    81 everything after the final dot. There is no restriction on the length of the

    81 </ul> <p>You will find that the whole structure is sometimes referred

    82 extension; limits on length apply to the whole structure, not to any single

    82 to as the full file name or the full path name. The maximum length

    83 part of it. </p> </li>

    83 of a full file name is limited to 256 characters. Symbian platform

    84 </ul> <p>You will find that the whole structure is sometimes referred to as

    84 does not use the extension to identify the software or application

    85 the full file name or the full path name. The maximum length of a full file

    85 that can access the data. Instead, files have UIDs embedded within

    86 name is limited to 256 characters. Symbian platform does not use the extension

    86 them, and the mapping of files to applications is done through these

    87 to identify the software or application that can access the data. Instead,

    87 UIDs. For more information, see <b>Symbian^3 Tools Guide &gt; Building</b>.</p> <p>The case of full path names is always preserved, but operations

    88 files have UIDs embedded within them, and the mapping of files to applications

    88 on names are case insensitive. This means that two files that have

    89 is done through these UIDs. See <xref href="GUID-3AFA877F-41DE-5343-8BC2-C0FB894A062C.dita">Application

    89 the same name but differ only in case are considered to refer to the

    90 registration information</xref>. </p> <p>The case of full path names is always

    90 same file. </p> <p>Full file names are normally manipulated programmatically.

    91 preserved, but operations on names are case insensitive. This means that two

    91 Extracting drive names, filenames, file extensions, and changing the

    92 files that have the same name but differ only in case are considered to refer

    92 names of a directory structure are typical activities. Symbian platform

    93 to the same file. </p> <p>Full file names are normally manipulated programmatically.

    93 provides you with the <xref href="GUID-E79A3B03-F8CB-37DB-A2A8-1C6C4E4D739A.dita"><apiname>TParse</apiname></xref>, <xref href="GUID-A6268E58-68EC-3041-93FD-5368CD230947.dita"><apiname>TParsePtr</apiname></xref>, and <xref href="GUID-C65BCDAB-0476-3EAC-9BFC-37243AE43FE9.dita"><apiname>TParsePtrC</apiname></xref> classes to help you do this manipulation. </p> <p>See <xref href="GUID-ECF9E432-EA93-5284-B0E6-A1211289CBD8.dita">parsing

    94 Extracting drive names, filenames, file extensions, and changing the names

    95 of a directory structure are typical activities. Symbian platform provides

    96 you with the <xref href="GUID-E79A3B03-F8CB-37DB-A2A8-1C6C4E4D739A.dita"><apiname>TParse</apiname></xref>, <xref href="GUID-A6268E58-68EC-3041-93FD-5368CD230947.dita"><apiname>TParsePtr</apiname></xref>, and <xref href="GUID-C65BCDAB-0476-3EAC-9BFC-37243AE43FE9.dita"><apiname>TParsePtrC</apiname></xref> classes

    97 to help you do this manipulation. </p> <p>See <xref href="GUID-ECF9E432-EA93-5284-B0E6-A1211289CBD8.dita">parsing

    99 <section id="GUID-62387DD0-D8E4-5426-8432-B14696291AF8"><title>Accessing file

    95 <section id="GUID-62387DD0-D8E4-5426-8432-B14696291AF8"><title>Accessing

   100 services</title> <p>On Symbian platform, file services are a common resource.

    96 file services</title> <p>On Symbian platform, file services are a

   101 Like other common or shared resources on Symbian platform, file services are

    97 common resource. Like other common or shared resources on Symbian

   102 handled by a server - the file server. Applications and other software that

    98 platform, file services are handled by a server - the file server.

   103 require access to files, directories and drives are clients of the file server,

    99 Applications and other software that require access to files, directories

   104 and send file-related requests using the <xref href="GUID-198DCED1-F429-5C95-A51D-53AE416687E8.dita">file

   100 and drives are clients of the file server, and send file-related requests

   105 server client-side API</xref>. </p> <p>The file server is multithreaded, which

   101 using the <xref href="GUID-198DCED1-F429-5C95-A51D-53AE416687E8.dita">file

   106 allows each logical drive to be accessed concurrently. More than one request

   102 server client-side API</xref>. </p> <p>The file server is multithreaded,

   107 can be issued for the same drive, but these requests are handled sequentially.

   103 which allows each logical drive to be accessed concurrently. More

   108 For example, a request to read or write data to a MultiMediaCard can be handled

   104 than one request can be issued for the same drive, but these requests

   109 at the same time as a request to read or write data to the main user drive. </p> <p>The

   105 are handled sequentially. For example, a request to read or write

   110 file server has a main thread that initially handles all requests. Short requests,

   106 data to a MultiMediaCard can be handled at the same time as a request

   111 such as those that require access to the ROM drive, and those that do not

   107 to read or write data to the main user drive. </p> <p>The file server

   112 require access to any media, run in the file server. </p> <p>The services

   108 has a main thread that initially handles all requests. Short requests,

   113 provided by the file server can be divided into two types: </p> <ul>

   109 such as those that require access to the ROM drive, and those that

   114 <li id="GUID-12F7606D-835D-5948-B0F0-EBACC5F6E569"><p>those that give you

   110 do not require access to any media, run in the file server. </p> <p>The services provided by the file server can be divided into two

   115 access to individual files, directories and drives using the <xref href="GUID-BE0804F6-4375-3C8A-8C83-968F510466E0.dita"><apiname>RFile</apiname></xref>, <xref href="GUID-12AE154F-7741-38C0-ADFE-9784FCF5E516.dita"><apiname>RDir</apiname></xref> and <xref href="GUID-9D7E765B-6872-3EB9-9D5B-1503FA466EC1.dita"><apiname>RFormat</apiname></xref> classes. </p> <p>See also <xref href="GUID-30B2AF3F-E120-5D47-AAA2-529555625B55.dita">How to

   111 types: </p> <ul>

   116 use sessions, files, and directories</xref>. </p> </li>

   112 <li id="GUID-12F7606D-835D-5948-B0F0-EBACC5F6E569"><p>those that give

   117 <li id="GUID-9E40CF33-C35E-52CE-80B9-8A019F34F305"><p>those that allow you

   113 you access to individual files, directories and drives using the <xref href="GUID-BE0804F6-4375-3C8A-8C83-968F510466E0.dita"><apiname>RFile</apiname></xref>, <xref href="GUID-12AE154F-7741-38C0-ADFE-9784FCF5E516.dita"><apiname>RDir</apiname></xref> and <xref href="GUID-9D7E765B-6872-3EB9-9D5B-1503FA466EC1.dita"><apiname>RFormat</apiname></xref> classes. </p> <p>See also <xref href="GUID-30B2AF3F-E120-5D47-AAA2-529555625B55.dita">How to use sessions,

   118 to do higher level longer running operations such as moving, copying and deleting

   114 files, and directories</xref>. </p> </li>

   119 files, using the <xref href="GUID-82CEC14F-1479-3922-846A-9FCDB6465EF7.dita"><apiname>CFileMan</apiname></xref> class, scanning directory trees

   115 <li id="GUID-9E40CF33-C35E-52CE-80B9-8A019F34F305"><p>those that allow

   120 using the <xref href="GUID-C657AF2D-1183-3CD2-ACAF-3B0B00FC91BB.dita"><apiname>CDirScan</apiname></xref> class, and tracking the progress of

   116 you to do higher level longer running operations such as moving, copying

   121 these operations using the <xref href="GUID-E608485F-B3E3-3310-A80E-169D8B9D2234.dita"><apiname>MFileManObserver</apiname></xref> class. </p> <p>See

   117 and deleting files, using the <xref href="GUID-82CEC14F-1479-3922-846A-9FCDB6465EF7.dita"><apiname>CFileMan</apiname></xref> class, scanning

   122 also <xref href="GUID-ACF6C0A2-87ED-55B3-B22A-9B331D9940AC.dita">File management

   118 directory trees using the <xref href="GUID-C657AF2D-1183-3CD2-ACAF-3B0B00FC91BB.dita"><apiname>CDirScan</apiname></xref> class, and tracking

   123 and searching</xref>  </p> </li>

   119 the progress of these operations using the <xref href="GUID-E608485F-B3E3-3310-A80E-169D8B9D2234.dita"><apiname>MFileManObserver</apiname></xref> class. </p> <p>See also <xref href="GUID-ACF6C0A2-87ED-55B3-B22A-9B331D9940AC.dita">File management and

   124 </ul> <p>Like most other servers, the client API allows you to make file requests

   120 searching</xref>.  </p> </li>

   125 synchronously or asynchronously. </p> <p>See also <xref href="GUID-6047DB3F-DC92-51DF-9EEB-00E79E890B54.dita">client-server</xref>. </p> </section>

   121 </ul> <p>Like most other servers, the client API allows you to make

   126 <section id="GUID-9FF4525A-EBFD-5E9F-BD86-C6B75E5C35EF"><title>Security issues</title> <p>Security

   122 file requests synchronously or asynchronously. </p> <p>See also <xref href="GUID-6047DB3F-DC92-51DF-9EEB-00E79E890B54.dita">client-server</xref>. </p> </section>

   127 considerations restrict the parts of a handset's directory structure that

   123 <section id="GUID-9FF4525A-EBFD-5E9F-BD86-C6B75E5C35EF"><title>Security

   128 an application is allowed to access. The concept is referred to as <i>data

   124 issues</title> <p>Security considerations restrict the parts of a

   129 caging</i>. </p> <p>There are a number of principles involved: </p> <ul>

   125 handset's directory structure that an application is allowed to access.

   130 <li id="GUID-21674EE5-40A3-5F71-9973-C089FD838585"><p>The fundamental principle

   126 The concept is referred to as <i>data caging</i>. </p> <p>There are

   131 is the separation of executable code from data. Executable code can only reside

   127 a number of principles involved: </p> <ul>

   132 in the <filepath>/sys/bin/</filepath> directory. Executables cannot be loaded

   128 <li id="GUID-21674EE5-40A3-5F71-9973-C089FD838585"><p>The fundamental

   133 from any location other than <filepath>/sys/bin/</filepath>. Unless an application

   129 principle is the separation of executable code from data. Executable

   134 has the appropriate system capabilities, the <filepath>/sys/</filepath> directory

   130 code can only reside in the <filepath>/sys/bin/</filepath> directory.

   135 is not visible to that application. System capabilities are a discrete set

   131 Executables cannot be loaded from any location other than <filepath>/sys/bin/</filepath>. Unless an application has the appropriate system

   136 of 'permissions' that give access to various sensitive system services, and

   132 capabilities, the <filepath>/sys/</filepath> directory is not visible

   137 which can only be granted to applications, if justified, through the <xref href="https://www.symbiansigned.com/app/page" scope="external">Symbian Signed</xref> scheme. </p> </li>

   133 to that application. System capabilities are a discrete set of 'permissions'

   138 <li id="GUID-4A1854CE-25CB-5630-A27C-73931D937567"><p>Applications have their

   134 that give access to various sensitive system services, and which can

   139 own private directory, under which they are free to create further directory

   135 only be granted to applications, if justified, through the <xref href="https://www.symbiansigned.com/app/page" scope="external">Symbian

   140 structures and files, and to write to those files. This is the directory structure <filepath>/private/&lt;app_SID&gt;/</filepath>. <i>&lt;app_SID&gt;</i> is known as a secure identifier and, in general, is used when verifying

   136 Signed</xref> scheme. </p> </li>

   141 an executable's rights of access to system resources. Here, it is used to

   137 <li id="GUID-4A1854CE-25CB-5630-A27C-73931D937567"><p>Applications

   142 form the path name for the executable's private directory. The secure identifier

   138 have their own private directory, under which they are free to create

   143 is a UID which is allocated to a developer through the <xref href="https://www.symbiansigned.com/app/page" scope="external">Symbian Signed</xref> scheme, and is guaranteed to be unique

   139 further directory structures and files, and to write to those files.

   144 within the handset on which the application is installed. The UID is coded

   140 This is the directory structure <filepath>/private/&lt;app_SID&gt;/</filepath>. <i>&lt;app_SID&gt;</i> is known as a secure identifier and, in general,

   145 into the <filepath>mmp</filepath> file(s) that define the application's source

   141 is used when verifying an executable's rights of access to system

   146 files, link requirements, and general characteristics. </p> <p>Other applications

   142 resources. Here, it is used to form the path name for the executable's

   143 private directory. The secure identifier is a UID which is allocated

   144 to a developer through the <xref href="https://www.symbiansigned.com/app/page" scope="external">Symbian

   145 Signed</xref> scheme, and is guaranteed to be unique within the handset

   146 on which the application is installed. The UID is coded into the <filepath>mmp</filepath> file(s) that define the application's source files,

   147 link requirements, and general characteristics. </p> <p>Other applications

   148 <li id="GUID-2814D086-A660-5294-9952-E6D66243B652"><p>There is a directory <filepath>/resource/</filepath> to

   149 <li id="GUID-2814D086-A660-5294-9952-E6D66243B652"><p>There is a directory <filepath>/resource/</filepath> to which all applications have read access,

   149 which all applications have read access, but no write access. The purpose

   150 but no write access. The purpose of this directory is to conatin common

   150 of this directory is to conatin common read-only files. </p> </li>

   151 read-only files. </p> </li>

   152 are accessible for both reading and writing. This allows the use of standard

   153 are accessible for both reading and writing. This allows the use of

   153 file system hierarchies that may be available on removable media. </p> </li>

   154 standard file system hierarchies that may be available on removable

   155 media. </p> </li>

   156 </ul> <p>It is possible to pass an open file to another process, or between

   158 </ul> <p>It is possible to pass an open file to another process, or

   157 a client and server, so that the target can access the file without knowing

   159 between a client and server, so that the target can access the file

   158 the full path name. The only information that is passed to the target is the

   160 without knowing the full path name. The only information that is passed

   159 filename and extension. </p> </section>

   161 to the target is the filename and extension. </p> </section>

   160 <section id="GUID-849F5D6E-7911-55F8-839A-019D1BF16726"><title>File systems

   162 <section id="GUID-849F5D6E-7911-55F8-839A-019D1BF16726"><title>File

   161 and mounting a drive</title> <p>The varying characteristics of media types

   163 systems and mounting a drive</title> <p>The varying characteristics

   162 can mean that different media types require different formats. A common format

   164 of media types can mean that different media types require different

   163 is VFAT, and typically, this is used for removable media to maintain compatibility

   165 formats. A common format is VFAT, and typically, this is used for

   164 with other systems. This also means that long file names are supported. </p> <p>In

   166 removable media to maintain compatibility with other systems. This

   165 Symbian platform, format schemes are implemented by what are called file systems;

   167 also means that long file names are supported. </p> <p>In Symbian

   166 they are constructed as plugins to the file server. This means that the file

   168 platform, format schemes are implemented by what are called file systems;

   167 server itself is independent of the format scheme, and also means that a phone

   169 they are constructed as plugins to the file server. This means that

   168 manufacturer is free to add new file systems to a handset. The ROM is an exception

   170 the file server itself is independent of the format scheme, and also

   169 - it has its own file system built into the main file server code. </p> <p>A

   171 means that a phone manufacturer is free to add new file systems to

   170 file system must be associated with a drive before the drive can be used.

   172 a handset. The ROM is an exception - it has its own file system built

   171 This is known as mounting the drive, and is typically done at system boot

   173 into the main file server code. </p> <p>A file system must be associated

   172 time. </p> <p>In practice, an application does not need to concern itself

   174 with a drive before the drive can be used. This is known as mounting

   173 with the format scheme. </p> </section>

   175 the drive, and is typically done at system boot time. </p> <p>In practice,

   176 an application does not need to concern itself with the format scheme. </p> </section>